江苏省无锡市天一实验学校、江阴初级中学、太湖格致中学2020届九年级下学期期中(一模)英语试题含答案
江苏省无锡市天一实验学校届九年级数学下学期第三次模拟试题(精选资料)
第9题图第8题图无锡市天一实验学校九年级三模数学试卷一、选择题：（本大题共10小题，每题3分，共30分．）1、下列图形中，既是轴对称图形，又是中心对称图形的是（ ▲ ） A ．正三角形 B ．平行四边形 C ．矩形 D ．等腰梯形2、计算32)2(b a -的结果是 （ ▲ ）A ．366b a - B ．b a 28- C ．362b a - D ．368b a -3、若a b 3a b 7+=-=，，则22a b -的值为 （ ▲ ） A ．－21 B ．21 C ．-10 D ．104（ ▲ ） A．12 D ．185、已知直角三角形ABC 的一条直角边AB=4cm ，另一条直角边BC=3 cm ，则以A B 为轴旋转一周，所得到的圆锥的侧面积是 （ ▲ ）A ．230cm πB ．215cm πC ．212cm πD ．220cm π6、在某校“我的中国梦”演讲比赛中，有15名学生参加决赛，他们决赛的最终成绩各不相同。
其中的一名学生想要知道自己能否进入前8名，不仅要了解自己的成绩，还要了解这15名学生成绩的（ ▲ ）.A ．众数B ．方差C ．平均数D ．中位数7、 若二次函数2()1y x m =--．当x ≤ 3时，y 随x 的增大而减小，则m 的取值范围是A ．m = 3B ．m >3C ．m ≥ 3D ．m ≤ 3 （ ▲ ）8、如图1所示，将一个正四棱锥（底面为正方形，四条侧棱相等）的其中四条边剪开，得到图2，则被剪开的四条边有可能是（ ▲ ）A ．PA ，PB ，AD ，BC B ．PD ，DC ，BC ，AB C ．PA ，AD ，PC ，BC D ．PA ，PB ，PC ，AD 9、如图，在直角坐标系中放置一个边长为2的正方形ABCD ，将正方形ABCD 沿x 轴的正方向无滑动的在x 轴上滚动，当点A 第三次回到x 轴上时，点A 运动的路线与x 轴围成的图形的面积和为（ ▲ ）A ．ππ+2B ．22+πC ．ππ323+D ．66+π10．如图，在△ABC 中，∠C =90°，AC =4，BC =2，点A 、C 分别在x 轴、y 轴上，当点A 在x 轴上运动时，点C 随之在y 轴上运动．在运动过程中，点B 到原点的最大距离是( ▲ ) A ．6 B ．2 6 C ．2 5 D ．22＋2第15题第18题第17题二、填空（本大题共8小题，每题2分，共16分） 11、函数xy -=11中自变量x 的取值范围是 ▲ ．12、我国因环境污染造成的巨大经济损失每年高达680000000元，这个数用科学记数法表示为 ▲ 元．13、已知点A （x 1，y 1）、B （x 1―3，y 2）在直线y ＝―2x ＋3上，则y 1 ▲ y 2 （用“＞”、“＜”或“＝”填空）14、若关于x 的二次方程032=+++a ax x 有两个相等的实数根，则实数a = ▲ 15、如图，点A 在双曲线x y 3=上，点B 在双曲线xy 5=上，且AB∥x 轴，C 、D 在x 轴上，若四边形ABCD 为平行四边形，则它的面积为 ▲16、如图，方格纸中有三个格点A 、B 、C ，则点A 到BC 的距离为＝ ▲ ．17、如图，正方形ABCD 的边长为1，中心为点O ，有一边长大小不定的正六边形EFGHIJ 绕点O 可任意旋转，在旋转过程中，这个正六边形始终在正方形ABCD 内（包括正方形的边），当这个六边形的边长最大时，AE 的最小值为_ _▲__18、如图所示，圆圈内分别标有1，2，…，12，这12个数字，电子跳蚤每跳一步，可以从一个圆圈逆时针跳到相邻的圆圈，若电子跳蚤所在圆圈的数字为n ，则电子跳蚤连续跳（3n-2）步作为一次跳跃，例如：电子跳蚤从标有数字1的圆圈需跳12-13=⨯步到标有数字2的圆圈内，完成一次跳跃，第二次则要连续跳42-23=⨯步到达标有数字6的圆圈，…依此规律，若电子跳蚤从①开始，第2016次电子跳蚤能跳到的圆圈内所标的数字为___▲__三、解答题（本大题共10小题，共84分） 19、（每小题5分，共10分）①解不等式组⎪⎩⎪⎨⎧+<≥+325,5)5.1(2m m m ，并将解集在数轴上表示出来 .②先化简，再求代数式的值:a a a a a -÷⎪⎭⎫⎝⎛+--+112122，其中13-=a .20、（本题满分6分）如图，线段AB 绕点O 顺时针旋转一定的角度得到线段A 1B 1． （1）请用直尺和圆规作出旋转中心O （不写作法，保留作图痕迹）；（2）连接OA 、OA 1、OB 、OB 1，如果∠AO A 1＝∠BOB 1＝α；OA ＝OA 1＝a ；OB ＝OB 1＝b ．则线段AB 扫过的面积是 ▲ ． 111210987654321B21、（本题满分6分）如图，E，F是四边形ABCD的对角线AC上两点，AF=CE，DF=BE，DF∥BE．求证：AB=CD22、（本题满分8分）在读书月活动中，学校准备购买一批课外读物．为使课外读物满足同学们的需求，学校就“我最喜爱的课外读物”从文学、艺术、科普和其他四个类别进行了抽样调查（每位同学只选一类），如图是根据调查结果绘制的两幅不完整的统计图．请你根据统计图提供的信息，解答下列问题：（1）本次调查中，一共调查了▲名同学；（2）条形统计图中，m= ▲，n= ▲；（3）扇形统计图中，艺术类读物所在扇形的圆心角是▲度；（4）学校计划购买课外读物5000册，请根据样本数据，估计学校购买其他类读物多少册比较合理？23、（本题满分7分）现有4根小木棒，长度分别为：2、3、3、5（单位：cm），从中任意取出3根，请用画树状图或例举法求它们能首尾顺次相接搭成三角形的概率．24、(本题满分8分)如图，某大楼的顶部树有一块广告牌CD，小李在山坡的坡脚A处测得广告牌底部D的仰角为60°．沿坡面AB向上走到B处测得广告牌顶部C的仰角为45°，已知山坡AB的坡度i=1：，AB=8米，AE=10米．（i=1：是指坡面的铅直高度BH与水平宽度AH的比）（1）求点B距水平面AE的高度BH；（2）求广告牌CD的高度．（测角器的高度忽略不计，结果精确到0.1米．）25、(本题满分9分)某景区门票价格80元/人，为吸引游客，对门票价格进行动态管理，非节假日打a折，节假日期间，10人以下（包括10人）不打折，10人以上超过10人的部分打b折，设游客为x人，门票费用为y元，非节假日门票费用y1（元）及节假日门票费用y2（元）与游客x（人）之间的函数关系如图所示．（1）a=___▲____，b=___▲_____（2）直接写出y1、y2与x之间的函数关系式；（3）导游小王4月15日（非节假日）带A旅游团，5月1日带B旅游团到该景区旅游，两团共计50人，两次共付门票费用3040元，求A、B两个旅游团各多少人？26．(本题满分10分)已知点O是四边形ABCD内一点，AB=BC，OD=OC，∠ABC=∠DOC=α．（1）如图1，α=60°，探究线段AD与OB的数量关系，并加以证明；（2）如图2，α=120°，探究线段AD与OB的数量关系，并说明理由；（3）结合上面的活动经验探究，请直接写出如图3中线段AD与OB的数量关系为▲（直接写出答案）27．(本题满分10分) 在平面直角坐标系xOy中，定义直线y=ax+b为抛物线y=ax2+bx的特征直线，C（a，b）为其特征点．设抛物线y=ax2+bx与其特征直线交于A、B两点（点A在点B的左侧）．（1）当点A的坐标为（0，0），点B的坐标为（1，3）时，特征点C的坐标为___▲___；28、(本题满分10分)如图，在平面直角坐标系中，O 为坐标原点，直线6+-=x y 交y 轴于点A ，交x 轴于点B ，点C 、B 关于原点对称，点P 在射线AB 上运动，连结CP 与y 轴交于点D ，连结BD ．过P 、D 、B 三点作⊙Q 与y 轴的另一个交点为E ，延长DQ 交⊙Q 于点F ，连结EF ，BF ． （1）求A 、B 、C 三点的坐标；（2）当点P 在线段AB （不包括A ，B 两点）上时．求证：DE=EF ；（3）请你探究：点P 在运动过程中，是否存在以B ，D ，F 为顶点的直角三角形，满足两条直角边之比为2：1？如果存在，求出此时点P 的坐标：如果不存在，请说明理由．。
江苏省无锡市2020-2021学年下学期九年级英语期中试卷分类汇编：阅读理解
江苏省无锡市2020-2021学年下学期九年级英语期中试卷分类汇编阅读理解江苏省无锡市2020—2021学年九年级下学期期中考试英语试卷三、阅读理解阅读下面的短文，然后根据短文内容，在每小题所给的四个选项中选出最佳选项。
（本大题共13小题，每小题2分，共26分）AEvery school has notice boards. Let’s see what is on the school boards of a middle school.Class AnnouncementTesting Dates:The Chinese test is on May 12The math test is on May 13.After-school Programs:The programs will be open from 3:00 p.m. to 6:00 p.m. every day.3:00-4:30 Doing homework4:30-6:00 Joining in ActivitiesParents Meeting:The parents meeting is at 8:00 a.m. on Friday, May 19 in the meeting hall.School PolicyFighting, saying rude words and all other bad behaviors are not allowed.Do not throw rocks or sticks on the school ground.Hand in a note if your child will be absent for the day.Parents need to check in at the school gate when entering the school.How to Keep Yourself Safe from Novel Coronavirus1. Wear masks outdoors.Make sure to wear it properly by tightening up the nose clip and pulling the bottom of it over your chin so that your nose and mouth are both covered.2. Cover your coughs and sneezes with napkins.Cover your mouth and nose with a napkin when you cough or sneeze, or you can cough or sneeze into your sleeve, but avoid covering with your hands directly.3. Wash your hands properly.25. From the school notice boards, we can know .A. students are not allowed to behave badlyB. parents meeting will be held in the gymC. after-school programs last two hours every dayD. parents need to hand in notes when entering the school26. To keep yourself safe fr om novel coronavirus, you’d better .A. pull the top of the mask over the mouthB. cover with your hands when coughingC. wash your hands with running water onlyD. do sports regularly to strengthen yourself27. Who are these notices most probably written to?A. Doctors and nurses.B. Parents and students.C. The school headmaster.D. Visitors to the school.BSeven years ago, Joyce Akinpe moved to Australia to start a new life, finding an exciting job in Sydney. After the outbreak (爆发) of COVID-19, she suddenly lost her job.Seeing that there were many others like herself in trouble from the outbreak, Akinpe and her two roommates, Michele Gomez and Maureen Lee, brainstormed ideas for how to help their local community. They came up with a street pantry（储藏柜）. Gomez said the idea was very simple, “Take what you need and leave what you can.”With the help of Gomez’s father, they built the Blessing Box – a street pantry, with shelves and hanging baskets and two doors made from old furniture.It sits just at the back of the three girls’ home, so they can look after it. They put some information notices into their neighbors’ mailboxes, and the Blessing Box was quickly filled with the donations (捐赠)from the community, “It is the community’s str ong support that keeps the project alive,” Akinpe said.We now have hundreds of people visiting our box every day. It might only a hours for the box to be full and next hour it might become empty again. “We are now helping others to carry outsimilar proj ects in their own communities, too”, Gomez said.Lee said things in the box were mostly convenience foods, as well as some necessary life things such as spaghetti and toilet paper. “Few people take everything at once. They think there are other people who need them more.” Lee added.There were many people rushing there for donations. The three girls needed to sanitize (消毒）all the donations and make sure all food packages were not broken. Gomez said that they had no time for rest, but what they did was well worth.28. Paragraph 2 mainly talks about ________.A. the way to build the Blessing BoxB. the help from the local communityC. the purpose of building a street pantryD. the trouble from the outbreak of COVID-1929. Put the following sentences in the right order according to the passage.a. The three girls thought up a good idea.b. The three girls received and sanitized the donations.c. The three girls put information notices into their neighbors’ mailboxes.d. The three girls buil t the Blessing Box with the help of Gomez’s father.A. c—a—b—dB. c—b—a—d.C. a—b—-d—cD. a—d—c—b30. Few people take everything they need at once because __________.A. they would like to use their own thingsB. they think other people need these things moreC. there aren’t enough donations in the Blessing BoxD. it's not safe to use the things from the Blessing BoxCHow much time do you spend looking at your smartphone, tablet or computer every day? These electronic devices help us m many ways, but they may also cause health problems.Too much screen time can cause eyestrain which leaves your eyes feeling dry and sore and could also affect your eyesight. To help your eyes stay healthy, follow the “20-20-20” rule: every 20 minutes, look at something 20 feet away for 20 seconds.Your eyes aren't the only parts of your body that could become worse from using electronic devices. People who write a lot of text messages can develop an injury called texting thumb". Therepeated movement of typing with thumbs can cause thumb and wrist pain and lead to the loss of grip strength （握力受损）.To avoid this, do this exercise: put a rubber band around the tips of your five fingers and open your hand to stretch the rubber band. Repeat this a few times.Scientific research suggests that electronic devices can also hurt your mind. One of the biggest problems is that using these devices can affect your sleep patterns. Doctors say the screen light stop you from feeling sleepy. So they advise people not to use electronic devices for at least one hour before trying to sleep.Another serious danger is Internet addiction （瘾）. Many people turn to the Internet to ease feelings of stress, sadness, and loneliness. Over time, they might start to depend on the Internet and feel worried if they're not connected To stop yourself from falling into this kind of trap, limit the amount of time you spend on line.To use your smartphone or computer safely, just make sure you follow these health tips. Also, remember that there is more to life than looking at an electronic screen.31. The first 20 of the "20-20-20"rule in the passage suggests________________.A. how long the break lastsB. how often you have the breakC. how far you look at objects from youD. how long you need to take a break32. Which picture best shows the rubber and exercise according to the passage?33. The underlined word "they" in Paragraph 5 refers to _________________.A. computer games or InternetB. feelings of stress, sadness and lonelinessC. several serious mind problemsD. people who have Internet addiction34. What's the passage mainly about?A. Electronic devices can hurt both your body and mind.B. Looking at screen for too long can cause sore eyes.C. Typing a lot can develop "texting thumb".D. The more you depend on the Internet, the less worried you might be.DThe woman was very frightened. What could she do? She dialed 999. The emergency calloperator Robert Naylor answered the call immediately."Please help me! It's in my bathroom! It's moving!" the woman cried. "What is it that's moving?" Robert answered calmly."A spider!" the woman shouted back at him.Robert believes that a significant number of the calls are not emergencies. The actual number across the country is close to 75%.Firstly, there are "silent calls". The emergency number is dialed, but when an operator answers, no one speaks. Often it's a small child or even a pet who has been playing with her phone and has accidentally rung the emergency number.Then there are "joke calls", often from teenagers. An operator answers the phone and the caller immediately hangs up. Robert believes these are declining, as there are far fewer public payphones these days. "People are less interested to make a call when they are doing it from their own mobile phone and they know we have their number!"The police always follow up both types of calls. It's a huge waste of money, the average (平均的) cost of responding to a silent or joke call is around ￡250.The great numbers of the none-emergency calls are like those from the woman above. A situation like this isn't an emergency. But this example is far from the worst. What do you think of the following?● A teenager girl in America called the police because her parents had decorated her room and she didn't like the color.● A mother in Italy rang the emergency services when her 16-year-old son refused to get out of the bed.● A Bra zilian teenage boy rang and asked the police to remove a video of him from YouTube. In the video, the boy was falling off his bike.There are many other examples, and most of these are from adults. These calls waste more than time and money. "If someone makes a joke call and the police manage to find them, then they can expect a fine of up to ￡5,000, and even a prison sentence (监禁)," warns Robert. "But for peoplewhose emergency aren't really serious, we simply try to deal with their calls as quickly as possible," he continues. "The person often quickly realizes their situation isn't really an emergency and ends up apologizing (道歉) for calling us. But if someone refuses to listen, then we have to hang up. Someone with a real emergency is probably waiting to speak to us."35. What does the underlined word "declining" probably mean?A. Getting serious.B. Turning worse.C. Getting useless.D. Becoming less.36. Why are there so many none-emergency calls?A. Operators give excellent service.B. Callers do not take any responsibilities.C. Dealing with none-emergency costs little.D. Many don't consider it an improper behavior.37. Which of the following is the best title for this passage?A. Emergency services.B. Is it an emergency?C. Different kinds of emergency calls.D. Who is to be responsible?答案：ADB CDB BBDA DDB江苏省江阴市青阳片2020-2021学年九年级下学期期中考试英语试题三、阅读理解（本大题共13 小题，每小题 2 分，共26 分）AIt's believed that people reach their mental peak (顶峰) in their 20s. However, this isn’t completely true. According to a recent study by scientists from the Massachusetts Institute of Technology in the US, people are best at doing different things at different ages. They studied many people aged 10 to 90 years old, who were asked to take part in different memory tests.25. At what age can people reach the peak of their attention?A. 2.B. 18.C. 43.D. 50.26. Which fact does the passage provide?A. The younger people are, the better memory they have.B. The study is based on some research on people of all ages.C. People in their 40s can understand others’ feelings best.D. Different people are good at different things at the same age.27. This passage is probably a(n)_____________________.A. novelB. report.C. advertisement.D. notice. BNEW DICOVERIES are popular among our students and let’s take a close look at what they are. 28._____________. To young children, a year might seem to last forever. But older people might say that it flies by. Why is that? According to US scientists, young people’s brains process information at a faster speed than older people. They take in more information and do more things in a day. Therefore, they feel like each day lasts longer. However, older people’s brains degrade (退化) as they age. They take in less information and thus see a day pass more quickly.A robot A sks for hugsLovot is a special robot from Japan. It cangive people comfort and warmth. It looks likea mix of a penguin ( 企鹅), an owl, and ateddy bear. Lovot has a camera on its head. Itcan remember about 1,000 faces. Wheelsunder Lovot’s body help the robot movearound. The fun thing about Lovot isreal-human. It can ask for a hug by openingits arms and waving to you, just like a baby.T A king 10,000 steps A d A yYou may have heard that walking 10,000 steps a day is good for your health. But is that true? In fact, there is no official recommendation to walk this much, US scientists said. It was an idea from an advertisement for Japanese pedometers (计步器) in the 1960s. Scientists suggest that people can have 150 minutes of moderate activity a week, such as quick walking. As a result walking about 7,000 to 8,000 steps a day is a good choice.28. Which may be suitable for 28 ?A. Time makes old people less wiseB. People of different ages see time differentlyC. Time has something to do with people’s ageD. Time flies faster to the young compared to the old29. Based on the paper, which of these is a fact?A. Lovot is good at remembering people’s faces .B. Each day lasts longer to the old people.C. Walking 10,000 steps a day is good for healthD. Robots are completely the same as the humans.30. According to the reading, which fits best in the “Cause” box below?A. Walking 10,000 steps a day may hurt your bones.B. Quick walking is the best form of exercise.C. Advertisements say the more exercise the better.D. Scientists think 150 minutes of moderate activity a week good for health.COne day, Bassanio came to visit Antonio. This was not unusual because they were good friends. But the visit was more important than usual for Bassanio. He already owed Antonio a lot of money, but now he wanted to borrow some more.“I have been spending more money than I earn,” began Bassanio. “I already owe you a lo t of Cause__________Effec t (结果) Walking about 7,000 to 8,000 steps a day is a good choicemoney. I will tell you how I am going to get enough money to pay back all the money I owe.”“Yes, tell me,” said Antonio. “If I can help you, I will.”“When I was a boy at school,” began Bassanio, “I sometimes lost a ball when I was playing. When that happened, I would throw another ball in exactly the same way and watch it carefully. I would often find the two balls together. You might think of your money that way. The money you gave me is the first ball. It is lost, and I Know it’s my fault. But if you gave me some more money, it could be like that second ball and help you get all the money back. I will give back the money you give me now as well as the money that I have already lost.”Antonio invited him to continue.Bassanio told him about a rich young lady in Belmont. Her name was Portia. Her father died and left her a lot of money. She was beautiful as well as rich, and she was not married. Many men came from all over the world to court her, but nobody had succeeded. Bassanio had met Portia before, and he knew that she liked him. He told Antonio that if he had enough money he would soon make her his wife.“She is rich and young and beautiful. Her hair is like gold, and her face is always sunny and happy. She is always smiling. Antonio! She is beautiful. She likes me. I am certain she would marry me, marry me!” he explained.Antonio laughed. “You are my friend, Bassanio,” he comforted. “and I will help you. You know that all my ships are at sea just now, so I do not have much money to give you. However, you can go into town and try to borrow the money. Tell the moneylenders that Antonio will guarantee the money is paid back to them. Don't worry!”31. How would Bassanio pay back Antonio’s money?A. He would use Antonio's money as “the first ball”.B. H e would use Antonio's money as “the second ball”.C. He would return the money with the help of relatives.D. He would borrow some money from the moneylenders.32. What does the underlined word “ guarantee” mean in the last paragraph?A. make sureB. worry aboutC. carry outD. work out33. What can you infer (推断) from the passage?A. Portia would refuse to meet Bassanio.B. Antonio didn't lend the money to Bassanio.C. Bassanio would go to Belmont and court Portia.D. Bassanio would pay all the money back to Antonio.DLearning to control our greatest fearsAlmost everyone is afraid of something, whether that’s snakes, heights, or public speaking.Fearing something is natural and common, and can even be helpful to frighten ourselves sometimes. In fact, fear can keep our bodies alert (警觉的) so we can act quickly to protect ourselves in the event of danger.But for some people, fear develops into a “phobia”, which is a strong and unreasonable fear of something. For example, most of us feel a little scared when looking down from a tall building . But people with terrible acrophobia — a fear of heights — may not only feel dizzy (头晕的) when faced with a great height, they may also even turn down a great job just because the company’s office is on a high floor of a building.Indeed, phobias can prevent some of us from living a normal life. According to Katherina Hauner, a researcher at Northwestern University in the US, people who are terribly scared of spiders might stay away from their home for days if they knew a spider was there.However, since it’s thought that fear comes from personal experiences or memories, some scientists believe it’s possible to “rewrite” these unpleasant memories, helping people get through their phobias.In a study by Hauner and other scientists, people with arachnophobia — a fear of spiders —were asked to first touch a spider with a paintbrush. Once they saw it wasn’t really dangerous, they then tried touching it while wearing a glove. Finally, they were able to hold it with their hands directly.Certain medicine has also been found to be helpful. Back in 2015, researchers at the University of Hiroshima in Japan injected (注射) a special medicine into a fish —which was afraid of light — to turn off the fear centre in its brain. From then on, the fish no longer feared light.While the search for ways to deal with phobias is making great progress, there’s still the question of whether getting rid of ( 去除) fear is a good idea or not. In fact, Dave Smithson ofthe charity Anxiety UK thinks it’s a bad idea. “It’s fear that prevents us from doing crazy things,” he said. “There’s a name for people who don’t have fear of consequences: psychopaths (精神变态者).”34. The main point of the article is to _________________.A. show us what kind of role fear plays in our livesB. discuss if it is good to try to get rid of fearC. tell us about fear and phobiaD. discuss scientific studies about fear35. How does the writer make the meaning of “phobia” clear?A. By making comparisons (比较).B. By giving examples.C. By giving statistics (数据).D. By giving lively descriptions (描述).36. Which of the following shows the progress scientists have made in finding ways to deal with phobias?A. They can use phobias to keep our bodies alert.B. They can now reduce the pain that is connected with the phobia.C. New medicine can shut off fear centers in animal brains whenever needed.D. They have succeeded in helping some people pay no attention to the bad memories connected with their phobia.37. Which of the following would Dave Smithson probably agree with?A. There is nothing to fear except fear itself.B. We should not let fear influence our decisions.C. Fear is not a completely bad thing.D. Without fear, everyone would be brave.答案：25. C 26. C 27. B 28. B 29. A 30. D 31. B 32. A 33. B 34. C 35. B 36. D 37. C江苏省江阴市要塞片2020-2021学年九年级下学期期中考试英语试题四、阅读理解（共13 小题, 每小题 2 分, 满分26 分）阅读下面的短文, 然后根据短文内容, 在每小题所给的四个选项中选出最佳选项。
无锡市天一学校九年级数学下册期中试卷(含答案解析)
无锡市天一学校九年级数学下册期中试卷(含答案解析)无锡市天一学校2021九年级数学下册期中试卷(含答案解析)一、选择题〔本大题共10小题，每题3分，共30分．在每题所给出的四个选项中，只要一项为哪一项正确的，请用2B 铅笔把答题卡上相应的选项标号涂黑〕1．以下各数中，属于在理数的是〔▲〕A． B． C． D．2．计算a2?a4的结果是〔▲〕A．a8 B．a6 C．2a6 D．2a83．2021年3月份，无锡市某周的日最高气温统计如下表：那么这七天中日最高气温的众数和中位数区分是〔▲〕A．4，4 B．5，4 C．4，3 D．4，4.54．左图是由八个相反的小正方体组合而成的几何体，那么其仰望图是〔▲〕5．如图，在四边形ABCD中，E、F、G、H区分是AB、BD、CD、AC的中点，要使四边形EFGH是菱形，那么四边形ABCD 只需求满足一个条件，是〔▲〕A．四边形ABCD是梯形 B．四边形ABCD是菱形C．对角线AC＝BD D．AD＝BC6．如图，OP平分∠MON，PA⊥ON于点A，点Q是射线OM上一个动点，假定PA＝3，那么PQ的最小值为〔▲〕A． B．2 C．3 D．27．如图，在平面直角坐标系中，过格点A、B、C作一圆弧，点B与以下格点的连线中，可以与该圆弧相切的是〔▲〕A．点(0，3) B．点(2，3) C点(5，1) D．点(6，1) 8.如图1,在△ABC中，∠ACB=90°，∠CAB=30°, △ABD是等边三角形，E是AB的中点，连结CE并延伸交AD于F，如图2，现将四边形ACBD折叠,使D与C重合，HK为折痕，那么sin∠ACH的值为〔▲〕A． B． C． D．9．假定不等式对恒成立，那么x的取值范围是〔▲〕A. B. C. D.10. 如图，用四个螺丝将四条不可弯曲的木条围成一个木框，不计螺丝大小，其中相邻两螺丝的距离依次为2、3、4、6，且相邻两木条的夹角均可调整．假定调整木条的夹角时不破坏此木框，那么恣意两个螺丝间的距离的最大值为〔▲〕A．6 B．7 C．8 D．10二、填空题〔本大题共8小题，每题2分，共16分．不需写出解答进程，只需把答案直接填写在答题卡上相应的位置处〕11．函数y＝中自变量x的取值范围是____▲____．12．因式分解：2m2－8m＋8＝____▲____．13．如图，AB、CD是水平放置的轮盘〔仰望图〕上两条相互垂直的直径，一个小钢球在轮盘上自在滚动，该小钢球最终停在阴影区域的概率为____▲____．14．如图，在四边形ABCD中，∠A＋∠B＝200°，∠ADC、ABCD的平分线相交于点O，那么∠COD的度数是____▲____．15．如图，一个扇形铁皮OAB，OA＝60 cm，∠AOB＝120°，小明将OA、OB合拢制成了一个圆锥形烟囱帽〔接缝疏忽不计〕，那么烟囱帽的底面圆的半径为____▲____．16．将量角器按如下图的方式放置在三角形纸片上，使点C 在半圆圆心上，点B在半圆上，边AB、AC区分交半圆于点E、F，点B、E、F对应的读数区分为160°、70°、50°，那么∠A的度数为____▲____．17.正方形ABCD、BEFG和矩形DGHI的位置如图，其中G、F 两点区分在BC、EH上。
江苏省无锡市太湖格致中学、江阴初级中学2020届九年级6月跟踪性测试物理试题(可编辑PDF版,无答案)
R3
A
B
R1
R2
第 11 题图
第 12 题图
图 12．如图所示电路，电源电压为 12V 且保持不变。闭合开关 S，当滑片 P 置于变阻器 的中点时，电压表的示数为 4V；当滑片 P 置于变阻器的 b 端时，定值电阻 R 在 10s 内产 生的热量为 60J。则下列结果正确的是 （ ） A．电路中的最小电流为 1.5A B．R 先后两次消耗的电功率之比为 8﹕9 C．R1 先后两次消耗的电功率之比为 4﹕3 D．滑片 P 在中点时，9s 内滑动变阻器 R 消耗的电能为 60J
A．若 K 是小孔并将光屏向右移动少许，光屏上的像将变模糊
B．若 K 是凸透镜，则它的焦距满足 f＞15cm
C．仅需水平移动 S、K 或 P 中的一个，即可判断 K 是否为小孔
D．若 K 是凸透镜并移至 35.0cm 刻度线处，光屏上将得到清晰的放大像
6．下列给出的现象中，物体运动状态没有发生改变的是（ ）
源，它属于＿＿＿＿＿（选填“可再生”或“不可再生”）能源。
14.烧水时水开后壶嘴周围有“白气”，且____(选填“a”或“b”)处较浓，这是
（填物态变化名称）现象．用温度计测量冰箱冷藏室的温度，往往在温度计的玻璃泡上裹
一小团湿棉花，这样做的好处是：
。
第 14 题图
第 15 题图
15.如图，让一束太阳光通过挡光板的狭缝照射到三棱镜的一个侧面上，慢慢转动三
A．苹果从树上落下
B．汽车匀速转弯
C．人造卫星绕地球匀速转动
D．货物被起重机吊起匀速上升
7．为了探究滑动摩擦力,小明同学利用牙刷做实验,当用力匀速拖动牙刷时,刷毛发
生了如图所示的弯曲,对这一实验的分析错误的是(
江苏省无锡市天一实验学校2020年九年级中考一模数学试题
初三中考第一次适应性训练数学试卷（考试时间为120分钟，试卷满分130分．）一、选择题（本大题共10小题，每小题3分，共30分．在每小题所给出的四个选项中，只有一项是正确的，请用2B铅笔把答题卡上相应的选项标号涂黑．．．．．．．．．．．．．）1．－3的绝对值是（▲）A．31B．31C．－3 D．32．下列运算正确的是（▲）A．743)(xx=B．532)(xxx-=⋅--C．23x x x+=D．222=x y x y++（）3．分解因式29a a-的结果是（▲）A．a（a− 9）B．（a− 3）（a＋3）C．（a− 3a）（a＋3a）D．2)3(-a4．如图，所给图形中是中心对称图形但不是轴对称图形的是( ▲)A B C D5．一次数学测试后，随机抽取九年级某班5名学生的成绩如下：91，78，98，85，98．关于这组数据说法错误．．的是（▲）A．极差是20 B．中位数是91 C．众数是98 D．平均数是916．圆锥的底面半径为2，母线长为4，则它的侧面积为( ▲ )A．4πB．8πC．16πD．43π7．如图是由几个相同的小正方体搭成的一个几何体，它的俯视图是（）8．在平面中，下列命题为真命题的是（▲）A．四边相等的四边形是正方形B．四个角相等的四边形是矩形C．对角线相等的四边形是菱形D．对角线互相垂直的四边形是平行四边形9.定义符号min{a，b}的含义为：当a≥b时min{a，b}=b；当a＜b时min{a，b}=a．如：min{1，﹣3}=﹣3，min{﹣4，﹣2}=﹣4．则min{﹣x2+1，﹣x}的最大值是（▲）A．B．C．1D．010.如图，在平面直角坐标中，直线l经过原点，且与y轴正半轴所夹的锐角为60°，过点A（0，1）作y轴的垂线交直线l于点B，过点B作直线l的垂线交y轴于点A1，以A1B、BA为邻边作□ABA1C1；过点A1作y轴的垂线交直线l于点B1，过点B1作直线l的垂线交y轴于点A2，以A2B1、B1A1为邻边作□A1B1A2C2；…；按此作法继续下去，则C n的坐标是（▲）A．（﹣×4n，4n）B．（﹣×4n-1，4n-1）C．（﹣×4n﹣1，4n）D．（﹣×4n，4n-1）A．B．C．D．二、填空题（本大题共8小题，每小题2分，共16分．不需写出解答过程，只需把答案直接填写在答题．．卡上相应的位置．．．．．．．处）11．函数2-=xy中自变量x的取值范围是▲。
江苏省无锡市天一实验学校2020—2021学年九年级下学期三月适应性考试语文试题
初三适应性练习（语文）（2021.3.）注意事项：1.本试卷分试题卷和答题卷两部分，所有答案一律写在答题卷上。
2.考试时间为 150 分钟，试卷满分为 130 分。
一、积累与运用（共20 分）1.根据课文默写（每空1分，共8 分）(1)醉里挑灯看剑，。
（辛弃疾《为陈同甫赋壮词以寄之》）（2），奉命于危难之间。
（诸葛亮《出师表》）（3）古今多少事，。
（陈与义《临江仙·夜登小阁，忆洛中旧游》）（4），灵旗空际看！（夏完淳《别云间》）（5）人生自古谁无死？。
（文天祥《过零丁洋》）（6）峰峦如聚，波涛如怒，。
（张养浩《山坡羊·潼关怀古》）（7）岑参《白雪歌送武判官归京》中与李白的“孤帆远影碧空尽，唯见长江天际流”有异曲同工之妙的句子是：“，。
”2.根据拼音写汉字。
（3 分）①diàn( )念②盘huán( ) ③不屑置biàn( )3.下列句子中加点词语使用不恰当的一项是（2分）（）A.小乐学习上，善于高效合理安排学习时间，生活中经常给同学们答疑解惑，这个学期荣膺．．学校“三好学生”。
B.《滕王阁序》汪洋恣肆，年轻的王勃一气呵成．．．．，让在座的文人墨客啧啧称奇。
C.他在困顿的生活面前渐渐失去了他曾经的洒脱，对人对事往往锱铢必较．．．．起来，真让人唏嘘不已啊。
D.桑桑的异想天开．．．．或者做出一些出人意料的古怪的行为，是一贯的。
4.下列句子顺序排列最恰当的一项（2分）（）①但是这些优秀并非万能，也不是一成不变的。
②客观情况、周围环境即使发生一丁点儿变化，优秀也可能变成劣势。
③一个人的知识、能力优势都是后天点滴积累的结果。
④如刻舟求剑，麻痹大意，更可能发生逆转，最终导致失败。
⑤因此，不能让经验主义冲淡了规律。
麻痹思想遮挡了双眼，从而败在了优势上。
A.②⑤①③④B.③①②④⑤C.③①④②⑤D.②⑤④①③5. 下列关于文学和文化常识表述不正确的一项是（2分）（）A.《曹刿论战》选自《左传》，相传是春秋时期左丘明根据鲁史编写的，这是一部编年体的史书，也是一部文学名著。
2019-2020学年江苏省无锡市锡山区天一实验学校九年级(下)开学数学试卷
2019-2020学年江苏省无锡市锡山区天一实验学校九年级（下）开学数学试卷一．选择题（共10小题，满分30分，每小题3分）1．（3分）3-的绝对值是( )A ．13-B ．3-C ．13D ．32．（3分）函数2x y x =-中自变量x 的取值范围是( ) A ．2x ≠ B ．2x C ．2x D ．2x >3．（3分）下列图形中，既是轴对称图形，又是中心对称图形的是( )A ．B ．C ．D ．4．（3分）某校有25名同学参加某比赛，预赛成绩各不相同，取前13名参加决赛，其中一名同学已经知道自己的成绩，能否进入决赛，只需要再知道这25名同学成绩的( )A ．最高分B ．中位数C ．方差D ．平均数5．（3分）已知2a b -=，则224a b b --的值为( )A ．2B ．4C ．6D ．86．（3分）如图，直径AB 为6的半圆，绕A 点逆时针旋转60︒，此时点B 到了点B '，则图中阴影部分的面积是( )A ．3πB ．6πC ．5πD ．4π7．（3分）下列判断错误的是( )A ．对角线互相垂直且相等的平行四边形是正方形B ．对角线互相垂直平分的四边形是菱形C ．对角线相等的四边形是矩形D ．对角线互相平分的四边形是平行四边形8．（3分）如图，A 经过点E 、B 、C 、O ，且(0,8)C ，(6,0)E -，(0,0)O ，则cos OBC∠的值为( )A ．35B ．45C ．34D ．3169．（3分）如图，将边长为10的等边三角形OAB 位于平面直角坐标系第一象限中，OA 落在x 轴正半轴上，C 是AB 边上的动点（不与端点A 、B 重合），作CD OB ⊥于点D ，若点C 、D 都在双曲线(0,0)k y k x x=>>上，则k 的值为( )A ．93B ．18C ．253D ．910．（3分）正方形ABCD 的边长为4，P 为BC 边上的动点，连接AP ，作PQ PA ⊥交CD 边于点Q ．当点P 从B 运动到C 时，线段AQ 的中点M 所经过的路径长( )A ．2B ．1C ．4D 2二．填空题（共8小题，满分16分，每小题2分）11．（2分）25的平方根是 ，16的算术平方根是 ，8-的立方根是 ．12．（2分）某人近期加强了锻炼，用“微信运动”记录下了一天的行走的步数为12400，将12400用科学记数法表示应为 ．13．（2分）若35m =，38n =，则23m n += ．14．（2分）圆锥底面圆的半径为2cm ，其侧面展开图的圆心角为120︒，则圆锥的母线长为cm ．15．（2分）如图，二次函数2(2)y x m =++的图象与y 轴交于点C ，与x 轴的一个交点为(1,0)A -，点B 在抛物线上，且与点C 关于抛物线的对称轴对称．已知一次函数y kx b =+的图象经过A ，B 两点，根据图象，则满足不等式2(2)x m kx b +++的x 的取值范围是 ．16．（2分）如图，四边形ABCD 内接于O ，//OC AD ，60DAB ∠=︒，106ADC ∠=︒，则OCB ∠= ︒．17．（2分）如图，Rt ABC ∆中，90ACB ∠=︒，4AC =，6BC =，D 为线段AC 上一动点，连接BD ，过点C 作CH BD ⊥于H ，连接AH ，则AH 的最小值为 ．18．（2分）如图，在ABC ∆中，6AB =，4AC =，30A ∠=︒，线段AB 上有一个动点P ，过点P 作//PD BC ，交AC 于D ，连接PC ，则PCD ∆的最大面积是 ．三．解答题（共10小题，满分84分）19．（8分）计算（1）011(3)2sin 45()8π--+︒-． （2）22(1)(3)(3)(1)a a a a +--+--．20．（5分）先化简，再求值：22169(2)11x x x x x -++-÷+-，其中2x =． 21．（12分）解方程：（1）2810x x -+=（2）23139x x x -=-- （3）解不等式组33213(1)8x x x x-⎧+⎪⎨⎪--<-⎩22．（8分）如图，ABCD 中，E 为AD 的中点，直线BE 、CD 相交于点F ．连接AF 、BD ．（1）求证：AB DF =；（2）若AB BD =，求证：四边形ABDF 是菱形．23．（6分）中华文化，源远流长，在文学方面，《西游记》、《三国演义》、《水浒传》、《红楼梦》是我国古代长篇小说中的典型代表，被称为“四大古典名著”，某中学为了了解学生对四大古典名著的阅读情况，就“四大古典名著你读完了几部”的问题在全校学生中进行了抽样调查，根据调查结果绘制成如图所示的两个不完整的统计图，请结合图中信息解决下列问题：（1）请将条形统计图补充完整；（2）本次调查所得数据的众数是部，中位数是部，扇形统计图中“1部”所在扇形的圆心角为度．（3）若该校共有800个人，那么看完3部以上（包含3部）的有多少人？24．（6分）在一个综艺节目中，主持人和两位嘉宾做一个互动游戏，在台上放置了四扇一样的门，门后各放有一张个人照，其中有两扇门后分别是两位嘉宾的个人照，现在主持人随机请一位嘉宾去随机开启一扇门，求恰好拿到这位嘉宾本人的个人照的概率．（请用“画树状图”或“列表”等方法写出分析过程）25．（7分）如图，已知在ABC∠=︒．∆中，90A（1）请用圆规和直尺作出P，使圆心P在AC边上，且与AB，BC两边都相切（保留作图痕迹，不写作法和证明）．（2）在（1）的条件下，若45AB=，P切BC于点D，求劣弧AD的长．∠=︒，1B26．（10分）甲、乙两车同时从A地出发，匀速开往B地．甲车行驶到B地后立即沿原路线以原速度返回A地，到达A地后停止运动；当甲车到达A地时，乙车恰好到达B地，并停止运动．已知甲车的速度为150/km h．设甲车出发xh后，甲、乙两车之间的距离为ykm，图中的折线OMNQ表示了整个运动过程中y与x之间的函数关系．（1）A、B两地的距离是km，乙车的速度是/km h；（2）指出点M的实际意义，并求线段MN所表示的y与x之间的函数表达式；（3）当两车相距150km时，直接写出x的值．27．（10分）我们知道，锐角三角函数可以揭示三角形的边与角之间的关系．为了解决有关锐角三角函数的问题，我们往往需要构造直角三角形．例如，已知1tan (090)3αα=︒<<︒，1tan (090)2ββ=︒<<︒，求αβ+的度数，我们就可以在图①的方格纸中构造Rt ABC ∆和Rt AED ∆来解决．（1）利用图①可得αβ+= ︒；（2）若3tan 2(045)4αα=︒<<︒，请在图②的方格纸中构造直角三角形，求tan α； （3）在矩形ABCD 中，AC 与BD 交于点O ，设(045)CAB αα∠=︒<<︒，请利用图③探究sin 2α、cos α和sin α的数量关系．28．（12分）如图1，在平面直角坐标系中，抛物线211384y x x =-++与x 轴交于A 、B 两点（点A 在点B 的右侧），与y 轴交于点C ，过点C 作x 轴的平行线交抛物线于点P ．连接AC ．（1）求点P 的坐标及直线AC 的解析式；（2）如图2，过点P 作x 轴的垂线，垂足为E ，将线段OE 绕点O 逆时针旋转得到OF ，旋转角为(090)αα︒<<︒，连接FA 、FC ．求23AF CF +的最小值； （3）如图3，点M 为线段OA 上一点，以OM 为边在第一象限内作正方形OMNG ，当正方形OMNG 的顶点N 恰好落在线段AC 上时，将正方形OMNG 沿x 轴向右平移，记平移中的正方形OMNG 为正方形O MNG '，当点M 与点A 重合时停止平移．设平移的距离为t ，正方形O MNG '的边MN 与AC 交于点R ，连接O P '、O R '、PR ，是否存在t 的值，使△O PR'为直角三角形？若存在，求出t的值；若不存在，请说明理由．2019-2020学年江苏省无锡市锡山区天一实验学校九年级（下）开学数学试卷参考答案与试题解析一．选择题（共10小题，满分30分，每小题3分）1．（3分）3-的绝对值是( )A ．13-B ．3-C ．13D ．3【解答】解：3-的绝对值是3．故选：D ．2．（3分）函数2xy x =-中自变量x 的取值范围是( )A ．2x ≠B ．2xC ．2xD ．2x >【解答】解：根据题意得：20x -≠，解得：2x ≠．故函数2xy x =-中自变量x 的取值范围是2x ≠．故选：A ．3．（3分）下列图形中，既是轴对称图形，又是中心对称图形的是() A ． B ．C ．D ．【解答】解：A 、是轴对称图形，不是中心对称图形，故此选项错误；B 、是轴对称图形，不是中心对称图形，故此选项错误；C 、是轴对称图形，是中心对称图形，故此选项正确；D 、不是轴对称图形，是中心对称图形，故此选项错误；故选：C ．4．（3分）某校有25名同学参加某比赛，预赛成绩各不相同，取前13名参加决赛，其中一名同学已经知道自己的成绩，能否进入决赛，只需要再知道这25名同学成绩的( )A ．最高分B ．中位数C ．方差D ．平均数【解答】解：某校有25名同学参加某比赛，预赛成绩各不相同，取前13名参加决赛，其中一名同学已经知道自己的成绩，能否进入决赛，只需要再知道这25名同学成绩的中位数． 故选：B ．5．（3分）已知2a b -=，则224a b b --的值为( )A ．2B ．4C ．6D ．8【解答】解：2a b -=，∴原式()()42()42242()4a b a b b a b b a b b a b =+--=+-=+-=-=，故选：B ．6．（3分）如图，直径AB 为6的半圆，绕A 点逆时针旋转60︒，此时点B 到了点B '，则图中阴影部分的面积是( )A ．3πB ．6πC ．5πD ．4π【解答】解：阴影部分的面积=以AB '为直径的半圆的面积+扇形ABB '的面积-以AB 为直径的半圆的面积=扇形ABB '的面积． 则阴影部分的面积是：26066360ππ⨯= 故选：B ．7．（3分）下列判断错误的是( )A ．对角线互相垂直且相等的平行四边形是正方形B ．对角线互相垂直平分的四边形是菱形C ．对角线相等的四边形是矩形D ．对角线互相平分的四边形是平行四边形【解答】解：A 、对角线互相垂直且相等的平行四边形是正方形，故本选项错误； B 、对角线互相垂直平分的四边形是菱形，故本选项错误；C 、对角线相等的四边形不一定是矩形，例如：等腰梯形的对角线相等，故本选项正确；D 、对角线互相平分的四边形是平行四边形，故本选项错误； 故选：C ．8．（3分）如图，A 经过点E 、B 、C 、O ，且(0,8)C ，(6,0)E -，(0,0)O ，则cos OBC∠的值为( )A ．35B ．45C ．34D ．316【解答】解：连接EC ，90COE ∠=︒，EC ∴是A 的直径，(0,8)C ，(6,0)E -，(0,0)O ，8OC ∴=，6OE =，由勾股定理得：10EC =，OBC OEC ∠=∠，63cos cos 105OE OBC OEC EC ∴∠=∠===． 故选：A ．9．（3分）如图，将边长为10的等边三角形OAB 位于平面直角坐标系第一象限中，OA 落在x 轴正半轴上，C 是AB 边上的动点（不与端点A 、B 重合），作CD OB ⊥于点D ，若点C 、D 都在双曲线(0,0)k y k x x=>>上，则k 的值为( )A ．93B ．18C ．253D ．9【解答】解：过点D 作DE x ⊥轴于点E ，过C 作CF x ⊥轴于点F ，如图所示． 可得：3030ODE BCD ∠=∠=︒，设OE a =，则2OD a =，3DE a =，102BD OB OD a ∴=-=-，2204BC BD a ==-，410AC AB BC a =-=-，1252AF AC a ∴==-，33(25)CF AF a ==-，152OF OA AF a =-=-， ∴点(,3)D a a ，点[152C a -，3(25)]a -．点C 、D 都在双曲线(0,0)k y k x x=>>上， 3(152)3(25)a a a a ∴=-⨯-，解得：3a =或5a =．当5a =时，DO OB =，AC AB =，点C 、D 与点B 重合，不符合题意，5a ∴=舍去．∴点(3D ，33)，33393k ∴=⨯=．故选：A ．10．（3分）正方形ABCD 的边长为4，P 为BC 边上的动点，连接AP ，作PQ PA ⊥交CD 边于点Q ．当点P 从B 运动到C 时，线段AQ 的中点M 所经过的路径长( )A．2B．1C．4D．2【解答】解：如图，连接AC，设AC的中点为O'．设BP的长为xcm，CQ的长为ycm．四边形ABCD是正方形，90B C∴∠=∠=︒PQ AP⊥，90APB QPC∴∠+∠=︒90APB BAP∠+∠=︒BAP QPC∴∠=∠ABP PCQ∴∆∆∽∴BP ABCQ PC=，即44xy x=-，2211(2)1(04)44y x x x x∴=-+=--+<<；∴当2x=时，y有最大值1cm．易知点M的运动轨迹是M O M→→，CQ最大时，1122 MO CQ==，∴点M的运动轨迹的路径的长为21OM=，故选：B．二．填空题（共8小题，满分16分，每小题2分）11．（2分）25的平方根是5±，16的算术平方根是，8-的立方根是．【解答】解：25的平方根是5±，16的算术平方根是4，8-的立方根是2-．故答案为：5±，4，2-．12．（2分）某人近期加强了锻炼，用“微信运动”记录下了一天的行走的步数为12400，将12400用科学记数法表示应为 41.2410⨯ ．【解答】解：412400 1.2410=⨯．故答案为：41.2410⨯．13．（2分）若35m =，38n =，则23m n += 200 ．【解答】解：35m =，38n =，2223(3)358200m n m n +∴=⨯=⨯=．故答案为：200．14．（2分）圆锥底面圆的半径为2cm ，其侧面展开图的圆心角为120︒，则圆锥的母线长为6 cm ．【解答】解：设圆锥的母线长为xcm ，根据题意得12022180x ππ=， 解得6x =，即圆锥的母线长为6cm ．故答案为6．15．（2分）如图，二次函数2(2)y x m =++的图象与y 轴交于点C ，与x 轴的一个交点为(1,0)A -，点B 在抛物线上，且与点C 关于抛物线的对称轴对称．已知一次函数y kx b =+的图象经过A ，B 两点，根据图象，则满足不等式2(2)x m kx b +++的x 的取值范围是 41x -- ．【解答】解：抛物线2(2)y x m =++经过点(1,0)A -，1m ∴=-，∴抛物线解析式为243y x x =++，∴点C 坐标(0,3)，∴对称轴为2x =-， B 与C 关于对称轴对称，点B 坐标(4,3)-，∴满足2(2)x m kx b +++的x 的取值范围为41x --，故答案为41x --．16．（2分）如图，四边形ABCD 内接于O ，//OC AD ，60DAB ∠=︒，106ADC ∠=︒，则OCB ∠= 46 ︒．【解答】解：//OC AD ，18074OCD ADC ∴∠=︒-∠=︒，四边形ABCD 内接于O ，180120BCD DAB ∴∠=︒-∠=︒，46OCB BCD OCD ∴∠=∠-∠=︒，故答案为：46．17．（2分）如图，Rt ABC ∆中，90ACB ∠=︒，4AC =，6BC =，D 为线段AC 上一动点，连接BD ，过点C 作CH BD ⊥于H ，连接AH ，则AH 的最小值为 2 ．【解答】解：90CHB ∠=︒，BC 是定值，H ∴点是在以BC 为直径的半圆上运动（不包括B 点和C 点），连接HO，则132HO BC==．90ACB∠=︒，4AC=，6BC=，2222435AO AC CO∴=+=+=，当A、H、O三点共线时，AH最短，此时532AH AO HO=-=-=．故答案为：2．18．（2分）如图，在ABC∆中，6AB=，4AC=，30A∠=︒，线段AB上有一个动点P，过点P作//PD BC，交AC于D，连接PC，则PCD∆的最大面积是32．【解答】解：如图，过点C作CE AB⊥于E，过点P作PF AC⊥于F，4AC=，30A∠=︒，122CE AC∴==，162ACBS AB CE∆∴=⨯⨯=，//PD BC，ADP ACB∴∆∆∽，∴2()ADPACBS ADS AC∆∆=，2616ADPADS∆∴=⨯，∴216216AD AD PF ⨯⨯=⨯， 34PF AD ∴=， 211333(4)(2)22482PCD S CD PF AD AD AD ∆=⨯⨯=⨯-⨯=--+， ∴当2AD =时，PCD ∆的最大面积32=， 故答案为：32． 三．解答题（共10小题，满分84分）19．（8分）计算（1）011(3)2sin 45()8π--+︒-． （2）22(1)(3)(3)(1)a a a a +--+--．【解答】解：（1）原式187=+=；（2）原式222292148a a a a a =+-+-+-=-．20．（5分）先化简，再求值：22169(2)11x x x x x -++-÷+-，其中2x =． 【解答】解：22169(2)11x x x x x -++-÷+- 22(1)(1)(1)(1)1(3)x x x x x x +--+-=++ 2221(1)(1)1(3)x x x x x x +-++-=++ 23(1)(1)1(3)x x x x x ++-=++ 13x x -=+， 当2x =时，原式211235-==+． 21．（12分）解方程：（1）2810x x -+=（2）23139x x x -=-- （3）解不等式组33213(1)8x x x x-⎧+⎪⎨⎪--<-⎩【解答】解：（1）2810x x -+=281x x -=-，2816116x x -+=-+，即2(4)15x -=，415x ∴∴-=±，1415x ∴=+，2415x =-；（2）去分母得，2(3)39x x x +-=-，去括号得，22339x x x +-=-，移项、合并同类项得，36x =-，系数化为1得，2x =-，经检验，2x =-是原方程的根；（3）()3321318x x x x -⎧+⎪⎨⎪--<-⎩①②，由①3x ；由②2x >-；∴原不等式组的解是23x -<．22．（8分）如图，ABCD 中，E 为AD 的中点，直线BE 、CD 相交于点F ．连接AF 、BD ．（1）求证：AB DF =；（2）若AB BD =，求证：四边形ABDF 是菱形．【解答】（1）证明：四边形ABCD 为平行四边形，//AB CD ∴．点F 在CD 的延长线上，//FD AB ∴．ABE DFE ∴∠=∠．E 是AD 中点，AE DE ∴=．在ABE ∆和DFE ∆中，ABE DFE BEA DEF AE DE ∠=∠⎧⎪∠=∠⎨⎪=⎩，()ABE DFE AAS ∴∆≅∆AB DF ∴=；（2）证明：ABE DFE ∆≅∆，AB DF ∴=．//AB DF ，AB DF =，∴四边形ABDF 是平行四边形．AB BD =，∴四边形ABDF 是菱形．23．（6分）中华文化，源远流长，在文学方面，《西游记》、《三国演义》、《水浒传》、《红楼梦》是我国古代长篇小说中的典型代表，被称为“四大古典名著”，某中学为了了解学生对四大古典名著的阅读情况，就“四大古典名著你读完了几部”的问题在全校学生中进行了抽样调查，根据调查结果绘制成如图所示的两个不完整的统计图，请结合图中信息解决下列问题：（1）请将条形统计图补充完整；（2）本次调查所得数据的众数是 1 部，中位数是 部，扇形统计图中“1部”所在扇形的圆心角为 度．（3）若该校共有800个人，那么看完3部以上（包含3部）的有多少人？【解答】解：（1）本次调查的学生有：1025%40⨯=（人)，读一部的有：402108614----=（人)，补全的条形统计图如右图所示；（2）本次调查所得数据的众数是1部，中位数是2部，扇形统计图中“1部”所在扇形的圆心角为：1436012640︒⨯=︒，故答案为：1、2、126；（3）8680028040+⨯（人)，∴看完3部以上（包含3部）的有280人．24．（6分）在一个综艺节目中，主持人和两位嘉宾做一个互动游戏，在台上放置了四扇一样的门，门后各放有一张个人照，其中有两扇门后分别是两位嘉宾的个人照，现在主持人随机请一位嘉宾去随机开启一扇门，求恰好拿到这位嘉宾本人的个人照的概率．（请用“画树状图”或“列表”等方法写出分析过程）【解答】解：设两位嘉宾为A、B，四张个人照分别为A、B、C、D，画树状图如下：由树状图可知共有8种等可能结果，其中恰好拿到这位嘉宾本人的个人照的有2种结果，所以恰好拿到这位嘉宾本人的个人照的概率为21 84 =．25．（7分）如图，已知在ABC∆中，90A∠=︒．（1）请用圆规和直尺作出P，使圆心P在AC边上，且与AB，BC两边都相切（保留作图痕迹，不写作法和证明）．（2）在（1）的条件下，若45B∠=︒，1AB=，P切BC于点D，求劣弧AD的长．【解答】解：（1）作法：作ABC ∠的角平分线交AC 于点P ，以点P 为圆心，AP 为半径作圆．证明：过P 作PD BC ⊥于D ， 90BAC ∠=︒，P ∴与AB 相切， BP 平分ABC ∠，AP PD ∴=， P 的半径是PA ，PD ∴也是P 的半径，即P 与BC 也相切；（2）如图，P 与AB ，BC 两边都相切， 90BAP BDP ∴∠=∠=︒，45ABC ∠=︒，360909045135APD ∴∠=︒-︒-︒-︒=︒， 45DPC ∴∠=︒，DPC ∴∆是等腰直角三角形， DP DC ∴=，在Rt ABC ∆中，1AB AC ==， 2CB ∴=BP BP =，AP PD =，Rt ABP Rt DBP ∴∆≅∆，1BD AB ∴==，21CD PD AP ∴==，∴劣弧AD 的长135(21)323π⨯--=．26．（10分）甲、乙两车同时从A 地出发，匀速开往B 地．甲车行驶到B 地后立即沿原路线以原速度返回A 地，到达A 地后停止运动；当甲车到达A 地时，乙车恰好到达B 地，并停止运动．已知甲车的速度为150/km h ．设甲车出发xh 后，甲、乙两车之间的距离为ykm ，图中的折线OMNQ 表示了整个运动过程中y 与x 之间的函数关系．（1）A 、B 两地的距离是600 km ，乙车的速度是 /km h ；（2）指出点M 的实际意义，并求线段MN 所表示的y 与x 之间的函数表达式；（3）当两车相距150km 时，直接写出x 的值．【解答】解：（1）A 、B 两地的距离是：150(82)600km ⨯÷=，乙车的速度为：600875/km h ÷=，故答案为：600，75；（2）点M 的实际意义是当甲车行驶4h 时，甲乙两车之间的距离为300km ，此时甲车达到B 地，点M 的坐标为(4,300)，设点N 的横坐标为n ，则150756002n n +=⨯，得163n =， ∴点N 的坐标为16(3，0)， 设线段MN 所表示的y 与x 之间的函数表达式是y kx b =+，43001603k b k b +=⎧⎪⎨+=⎪⎩，得2251200k b =-⎧⎨=⎩，即线段MN所表示的y与x之间的函数表达式是16 2251200(4)3 yx x=-+；（3）设OM段对应的函数解析式为y ax=，3004a=，得75a=，OM∴段对应的函数解析式为75y x=，令75150x=，得2x=，MN段对应的函数解析式为2251200y x=-+，∴当2251200150x-+=时，得143x=，设过点16(3N，0)、(8,600)Q的函数解析式为y cx d=+，1638600c dc d⎧+=⎪⎨⎪+=⎩，得2251200cd=⎧⎨=-⎩，即2251200y x=-，令2251200150x-=，得6x=，答：当两车相距150km时，x的值是2、143或6．27．（10分）我们知道，锐角三角函数可以揭示三角形的边与角之间的关系．为了解决有关锐角三角函数的问题，我们往往需要构造直角三角形．例如，已知1tan(090)3αα=︒<<︒，1tan(090)2ββ=︒<<︒，求αβ+的度数，我们就可以在图①的方格纸中构造Rt ABC∆和Rt AED∆来解决．（1）利用图①可得αβ+=45︒；（2）若3tan2(045)4αα=︒<<︒，请在图②的方格纸中构造直角三角形，求tanα；（3）在矩形ABCD中，AC与BD交于点O，设(045)CABαα∠=︒<<︒，请利用图③探究sin2α、cosα和sinα的数量关系．【解答】解：（1）如图①，连接CD，2221310AC =+=，222125CD =+=，222125AD =+=，222CD AD AC ∴+=，且CD AD =，ACD ∴∆是等腰直角三角形，45CAD ∴∠=︒，即45αβ+=︒，故答案为：45．（2）构造如图②所示Rt ABC ∆，3AC =，4CB =，5AB =，设2ABC α∠=，在Rt ABC ∆中，90C ∠=︒，3tan 2tan 4ABC α=∠=， 延长CB 到D ，使BD AB =，5AB BD ==，BAD D ∴∠=∠，2ABC D ∴∠=∠，D α∴∠=，在Rt ADC ∆中，90C ∠=︒，31tan tan 93AC D CD α∴=∠===；（3）如图③，过点C 作CE BD ⊥于E ，四边形ABCD 是矩形，12AO CO AC ∴==，12BO DO BD ==，AC BD =， OA OB ∴=，OAB OBA α∴∠=∠=，2COB α∠=，在Rt OCE ∆中，90ABC ∠=︒， 则2sin 2CE CE OC ACα==， 在Rt ACB ∆中，90ACB ∠=︒， 则sin CB AC α=，cos AB ACα=， OC OB =，CBE ACB ∴∠=∠，90CEB ABC ∠=∠=︒，CEB ABC ∴∆∆∽， ∴CE BC AB AC=， AB BC CE AC ∴=， ∴2222CE AB BC CB AB AC AC AC AC==，即sin22sin cos ααα=． 28．（12分）如图1，在平面直角坐标系中，抛物线211384y x x =-++与x 轴交于A 、B 两点（点A 在点B 的右侧），与y 轴交于点C ，过点C 作x 轴的平行线交抛物线于点P ．连接AC ．（1）求点P 的坐标及直线AC 的解析式；（2）如图2，过点P 作x 轴的垂线，垂足为E ，将线段OE 绕点O 逆时针旋转得到OF ，旋转角为(090)αα︒<<︒，连接FA 、FC ．求23AF CF +的最小值；（3）如图3，点M 为线段OA 上一点，以OM 为边在第一象限内作正方形OMNG ，当正方形OMNG 的顶点N 恰好落在线段AC 上时，将正方形OMNG 沿x 轴向右平移，记平移中的正方形OMNG 为正方形O MNG '，当点M 与点A 重合时停止平移．设平移的距离为t ，正方形O MNG '的边MN 与AC 交于点R ，连接O P '、O R '、PR ，是否存在t 的值，使△O PR '为直角三角形？若存在，求出t 的值；若不存在，请说明理由．【解答】解：（1）在抛物线211384y x x =-++中， 当0x =时，3y =，(0,3)C ∴，当3y =时，10x =，22x =，(2,3)P ∴，当0y =时，14x =-，26x =，(4,0)B -，(6,0)A ，设直线AC 的解析式为3y kx =+，将(6,0)A 代入， 得，12k =-， 132AC y x ∴=-+， ∴点P 坐标为(2,3)P ，直线AC 的解析式为132AC y x =-+；（2）在OC 上取点4(0,)3H ，连接HF ，AH ， 则43OH =，22224285()63AH OH OA =+=+=， 42323OH OF ==，23OF OC =，且HOF FOC ∠=∠， HOF FOC ∴∆∆∽，∴23HF CF =， 23HF CF ∴=， 223AF CF AF HF AH ∴+=+=，23AF CF ∴+；（3）正方形OMNG 的顶点N 恰好落在线段AC 上， CN MN ∴=，∴设(,)N a a ，将点N 代入直线AC 解析式，得，132a a =-+， 2a ∴=，∴正方形的边长是2，平移的距离为t ，∴平移后OM 的长为2t +，6(2)4AM t t ∴=-+=-，//RM OC ，ARM ACD ∴∆∆∽，∴AM RM OA OC=， 即463t RM -=， 122RM t ∴=-， 如图31-，当90O RP '∠=︒时，延长RN 交CP 的延长线于Q ， 90PRQ O RM '∠+∠=︒，90RO M O RM ''∠+∠=︒，PRQ RO M '∴∠=∠，又90Q O MR '∠=∠=︒，PQR RMO '∴∆∆∽，∴PQ QR RM MO ='，PQ t =，1312QR RM t =-=+， ∴1121222t t t +=-，解得，13t =--，23t =；如图32-，当90PO R '∠=︒时，90PO E RO M ''∠+∠=︒，90PO E EPO ''∠+∠=︒，RO M EPO ''∴∠=∠，又90PEO O MR ''∠=∠=︒，PEO '∴∆∽△O MR '， ∴PE EO O M RM'='， 即321222t t -=-， 解得，207t =；如图33-，当90O PR '∠=︒时，延长OG 交CP 于K ，延长MN 交CP 的延长线于点T ， 90KPO TPR '∠+∠=︒，90KO P KPO ''∠+∠=︒，KO P TPR '∴∠=∠，又90O KP T '∠=∠=︒，∴△KO P TPR '∆∽， ∴KP KO TR PT'=， 即2313(2)2ttt -=--， 整理，得23102t t ++=， △27404b ac =-=-<， ∴此方程无解，故不存在90O PR '∠=︒的情况；综上所述，△O PR '为直角三角形时，t 的值为173-或207．。
2020年江苏省无锡市天一实验学校、江阴中学、太湖格致中学中考化学一模试卷 解析版
2020年江苏省无锡市天一实验学校、江阴中学、太湖格致中学中考化学一模试卷一、选择题（共15小题，每小题1分，满分15分）1．（1分）党的十九大对生态文明建设和生态环境保护提出了一系列新理念、新要求、新目标和新部署，为未来人与自然的和谐相处提供了行动指南。
下列行为符合“尊重自然，自觉践行绿色生活”理念的是（）A．“能开车就不步行”提高出行效率，彰显城市发达程度B．燃放烟花爆竹，增强节日气氛C．经常使用一次性筷子、塑料袋等D．推广秸秆综合利用，杜绝露天焚烧2．（1分）下列物质的用途中，利用其物理性质的是（）A．活性炭吸附色素B．硫酸除锈C．氧气用于气焊D．生石灰用作干燥剂3．（1分）下列实验现象描述正确的是（）A．硫在氧气中燃烧产生淡蓝色火焰B．镁条和稀盐酸反应放出大量的热C．铁锈与稀盐酸反应溶液变成浅绿色D．碳还原氧化铜生成铜4．（1分）下列实验方案或操作不正确的是（）A．证明CO2与NaOH溶液发生了反应B．用碳酸钠溶液鉴别盐酸和石灰水C．探究燃烧的三个条件D．稀释浓硫酸5．（1分）下列物质俗称、化学式相符合的一组是（）A．火碱Na2CO3B．熟石灰CaOC．生石灰CaCO3D．烧碱NaOH6．（1分）下列关于四种粒子结构示意图的说法正确的是（）A．①③属于不同种元素B．④属于离子，离子符号为Mg2﹣C．②③的化学性质相似D．①④均达到相对稳定的结构7．（1分）受损元素周期表中某元素的残留信息如图所示，根据残留信息得出的下列说法中错误的是（）A．该元素是金属元素，原子序数为11B．该元素符号为MgC ．该元素的原子结构示意图为D．该元素的原子在化学反应中易失去电子8．（1分）下列气体中，既可以用浓硫酸干燥，又可以用固体氢氧化钠干燥的是（）A．二氧化硫B．氢气C．二氧化碳D．氨气9．（1分）高锰酸钾和浓盐酸发生如下应：2KMnO4+16HCl═2KCl+2MnCl2+5X↑+8H2O，根据质量守恒定律，推测X应是（）A．HClO B．ClO2C．O2D．Cl210．（1分）氯化铵和硝酸钾溶解度曲线如图所示，下列叙述正确的是（）A．硝酸钾的溶解度比氯化铵的大B．a℃时，氯化铵与硝酸钾溶液中溶质的质量分数相等C．将20℃的硝酸钾不饱和溶液升温可以变为饱和溶液D．40℃时，50g水中加入50g硝酸钾，充分搅拌，得到质量分数为39.02%的硝酸钾溶液11．（1分）某同学对所学部分化学知识归纳如下，其中有错误的一组是（）A物质性质与用途B日常生活经验N2不活泼﹣可作保护气H2O2分解放出O2﹣实验室制O2衣服上圆珠笔油﹣用汽油或酒精搓洗区别棉和羊毛织物﹣取少量，点燃闻气味C安全常识D化学与生活住宅失火时用水浇灭﹣降低可燃物着火点皮肤沾上浓硫酸﹣用水冲洗，再涂氢氧化钠维生素C﹣缺乏时引起坏血病糖类、蛋白质﹣必需摄取的营养素A．A B．B C．C D．D12．（1分）下列物质间的转化，不能由一步反应实现的是（）A．Fe→FeSO4B．CO2→CaCO3C．KNO3→K2CO3D．HCl→CuCl2 13．（1分）下列曲线能正确表达对应的反应或过程的是（）A ．NH4NO3固体溶于水B ．煅烧石灰石C ．等质量等浓度的稀H2SO4加入金属D ．CuSO4和H2SO4混合液中加入NaOH14．（1分）中考复习阶段，小胖梳理了以下知识：①均一、稳定的液体一定是溶液；②向某固体上滴加稀盐酸，有气泡产生，则该固体不一定是碳酸盐；③有盐和水生成的反应一定是中和反应；④配制6%的氯化钠溶液，量取水时，仰视量筒刻度使所配氯化钠溶液的质量分数偏低；⑤粗盐提纯时需把蒸发皿中的水蒸干才能停止加热；⑥盐能解离出酸根离子，能解离出酸根离子的化合物一定是盐；其中正确的个数是（）A．5B．4C．3D．215．（1分）有一包白色粉末，可能含有Na2CO3、Na2SO4、K2SO4、KCl、Ba（OH）2中的一种或几种，为了探究其成分，实验过程如图所示：关于该实验的说法中，正确的是（）A．步骤Ⅱ中沉淀不溶解，则原白色粉末一定有K2SO4，一定没有Na2CO3B．步骤Ⅱ中沉淀全部溶解，则原白色粉末一定有Ba（OH）2、Na2CO3，可能有KClC．步骤Ⅱ中沉淀部分溶解，则原白色粉末一定有Ba（OH）2、Na2CO3、K2SO4D．步骤Ⅱ中沉淀部分溶解，则原白色粉末的组成可能有3种情况二、填空题（共2小题，每小题4分，满分8分）16．（4分）写出符合下列要求的化学用语。
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2019-2020学年第二学期期中考试初三英语试卷（考试时间：100分钟满分：90分）第I卷（客观题共50分）一、单项填空在A、B、C、D四个选择中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
（本大题共14小题，每小题1分，共14分）1. --Have you heard of Li Wenliang , doctor in Wuhan Central Hospital?-- Yes, it's said that he was one of first men to remind people of the coronavirus.A. a; theB. the; aC. a; aD. / ; the2. --Joan is not so quick, but she has a good habit of working hard, it is like a hidden .A. competitionB. treasureC. traditionD. influence3. --The frozen yogurt tastes like ice cream but has of the fat.--It suits my mother, she is on a diet.A. anyB. neitherC. someD. none4. –Where was Mr John at that time?- -Em, we found the robot. Something was wrong with it.A. him fixingB. he fixedC. that he fixedD. he fixing5.--May I speak to Mr. Green?--Sorry, the wrong number. Please to 114 and check the number.A. go throughB. look throughC. run throughD. put through6. Many scientists believe human beings will face more serious problems ______they take action to change the way they live.A. butB. thoughC. unlessD. until7. --This task is really beyond me.-- Well. if you_______ solve it, you won’t get paid.A. needn’tB. can’tC. shouldn’tD. mustn’t8. We found him __________ with. He’s quite an easy-going guy.A. easily to workB. easily workingC. easy to workD. easy working9. --Look at Ann. How pale she looks!--Well, she never eats ________ and that’s why she is not healthy.A. rapidlyB. smoothlyC. completelyD. properly10.--Do you know in Tokyo?--It will be put off, but the date hasn't been decided yet.A. when will the 32nd Olympic Games take placeB. when the 32nd Olympic Games will be heldC. when will the 32nd Olympic Games be heldD. when the 32nd Olympic Games will be taken place11.--I hear that we may have to be at school on Saturday this term!--What?! I've never heard of idea before.A. a crazierB. the crazierC. a craziestD. the craziest12. --It's said that Chris achieved high grades in the exam.-- That's no surprise .He is______________, you know.A. a dark horseB. a green handC. an early birdD. a wet blanket13. --May I go to the cinema with Tom tomorrow, mom?--Of course, if your homework _______ by then.A. will be finishedB. finishC. will finishD. is finished14. --The music is too loud. Could you turn it down, please?--_______________.A. Really? Thank you for telling meB. Sorry , I didn't noticeC. Well, I'm glad to hear thatD. It's my pleasure二、完形填空先通读下面的短文，掌握其大意，然后在每小题所给的四个选项中，选出可以填入空白处的最佳选项,并在答题卡上将该项涂黑。
（本大题共10小题，每小题1分，共10分）Chef Zhang Xuesi lowered the fire on the stove where he was cooking his Cantonese meal. He added all the necessary foods, 15_the seafood, shrimp. He quickly lowered the fire and turned toward a phone camera 16hundreds of people watched him online.Many people in China have to stay in their homes in the effort to stop the 17of coronavirus. Millions of them are finding a new interest in cooking.People watching television and online cooking shows are learning 18 to make Chinese and Western foods. They are also pushing up the sale of special cookware on online markets.The Chinese video streaming company Billibilli said it has had more than 580 million views of its 19 videos in the two months since Another online cooking show producer DayDayCook told Reuters its numbers of new users 20 200 percent from January to February. A recipe for bean curd and shrimp received the most watchers."We have never gained new users with such speed since we launched the 21in 2012," said founder and leader Norma Chu. Many new home cooks are young people living in cities, say industry leaders. This group is used to 22in restaurants or getting food delivery. Now these people are cooking at home.Wu Shuang is a 30-year-old who works in Beijing, the capital. She was 23those trapped at home in February. She says she spent a lot of time online, learning how to make bread and other foods. Chef Zhang explained that many of his online viewers expressed 24in discussing more than just food.15 A. including B. forgetting C. having D. remembering16 A. why B. before C. as D. after17 A. coming B. spread C. return D. birth18 A. what B. where C. when D. how19 A. cooking B. fire C. dancing D. singing20 A. got B. increased C. reduced D. became21 A. service B. beginning C. ending D. actions22 A. playing B. eating C. drinking D. buying23 A. between B. besides C. opposite D. among24 A. feeling B. humour C. interest D. anger三、阅读理解阅读下面短文，根据短文内容，在每小题所给的四个选项中选出最佳选项,并在答题卡上将该项涂黑。