2018秋初二天津市和平区期中考试试卷
天津市和平区八年级下数学期中复习试卷有答案-精校
2018年八年级数学期中复习试卷一、选择题:1.函数y=自变量的取值范围是（）A．x≠﹣3 B．x＞﹣3 C．x≥﹣3 D．x≤﹣32.下列计算正确的是( )A．(3a)2=6a2B．(-3)-2=6 C=-2 D=3.若三边长满足，则是( )A．等腰三角形B．等边三角形C．直角三角形D．等腰直角三角形4.如图,在平行四边形ABCD中,∠BAD的平分线交BC于点E,∠ABC的平分线交AD于点F,若BF=12,AB=10,则AE的长为（）A．13 B．14 C．15 D．165.下列计算正确的是（）A．B．C．D．6.如图，在菱形ABCD中，E，F分别在AB，CD上，且BE=DF，EF与BD相交于点O，连结AO．若∠CBD=35°，）A．35°B．55°C．65°D．75°7.若一个三角形的三边长分别为6、8、10，则这个三角形最长边上的中线长为（）A．3.6 B．4 C．4.8 D．58.如图,将一个矩形纸片ABCD，沿着BE折叠，使C、D点分别落在点C，D1处．若∠C1BA=50°，则∠ABE的1度数为（）A．15°B．20°C．25°D．30°9.下列命题中,真命题是（）A．对角线相等的四边形是矩形 B.对角线互相垂直的四边形是菱形C.对角线互相平分的四边形是平行四边形D.对角线互相垂直平分的四边形是正方形10.如图，已知菱形OABC的顶点O（0，0），B（2，2），若菱形绕点O逆时针旋转，每秒旋转45°，则第60秒时，菱形的对角线交点D的坐标为( )A．(1，-1) B．(-1，-1) C．(2，0) D．(0，-2)二、填空题:11.点Q（5，﹣12）到原点的距离是．12.函数y=的自变量的取值范围是13.如图，在Rt△ABC中，∠ACB=90°，点D、E、F分别是AB、AC、BC中点，若CD=5，则EF长为.14..E为□ABCD边AD上一点，将ABE沿BE翻折得到FBE，点F在BD上,且EF=DF．若∠C=52°，则∠ABE=______15.如图，矩形ABCD的对角线AC，BD相交于点O，分别过点C，D作BD，AC的平行线，相交于点E．若AD=6，则点E到AB的距离是________．16.如图，在等边△ABC中，AB=6，N为线段AB上的任意一点，∠BAC的平分线交BC于点D，M是AD上的动点，连结BM、MN，则BM+MN的最小值是 .三、解答题:17.计算：18.计算：19.如图，已知在△ABC中，D是BC的中点，DE⊥BC，垂足为D，交AB于点E，且BE2﹣EA2=AC2，①求证：∠A=90°．②若DE=3，BD=4，求AE的长．20.如图,四边形ABCD中,AD∥BC,AE⊥AD交BD于点E,CF⊥BC交BD于点F,且AE=CF．求证：四边形ABCD是平行四边形．21.如图所示,在菱形ABCD中,AB=2,∠DAB=60°,点E是AD边的中点,点M是AB边上一动点(不与点A重合),延长ME交射线CD于点N,连接MD,AN.(1)求证:四边形AMDN是平行四边形;(2)①当AM为何值时,四边形AMDN是矩形?②当AM为何值时,四边形AMDN是菱形?22.已知E,F分别为正方形ABCD的边BC,CD上的点,AF,DE相交于点G,当E,F分别为边BC,CD的中点时,有AF=DE,AF⊥DE成立.试探究下列问题:(1)如图①,若点E不是边BC的中点,F不是边CD的中点,且CE=DF,上述结论是否仍然成立?(请直接回答“成立”或“不成立”,不需要证明)(2)如图②,若点E,F分别在CB的延长线和DC的延长线上,且CE=DF,此时,上述结论是否仍然成立?若成立,请写出证明过程,若不成立,请说明理由;(3)如图③,在(2)的基础上,连接AE和EF,若点M,N,P,Q分别为AE,EF,FD,AD的中点,请判断四边形MNPQ是“矩形、菱形、正方形”中的哪一种,并证明你的结论.参考答案1.B.2.D.3.C4.A5.B．6.D.7.B8.B.9.A.10.B.11.答案为：13．12.答案为：≥﹣3且x≠﹣1 ．13.答案为：514.答案为：5115.答案为：916.答案为：;17.解：原式=0；18.解：原式=919.（1）证明：连接CE，如图，∵D是BC的中点，DE⊥BC，∴CE=BE…（2分）∵BE2﹣EA2=AC2，∴CE2﹣EA2=AC2，∴EA2+AC2=CE2，∴△ACE是直角三角形，即∠A=90°；（2）解：∵DE=3，BD=4，∴BE==5=CE，∴AC2=EC2﹣AE2=25﹣EA2，∵BC=2BD=8，∴在Rt△BAC中由勾股定理可得：BC2﹣BA2=64﹣（5+EA）2=AC2，∴64﹣（5+AE）2=25﹣EA2，解得AE=1.4．20.证明：∵AE⊥AD，CF⊥BC，∴∠EAD=∠FCB=90°，∵AD∥BC，∴∠ADE=∠CBF，在Rt△AED和Rt△CFB中，∵，∴Rt△AED≌Rt△CFB（AAS），∴AD=BC，∴四边形MNPQ是正方形。
天津市和平区2018-2020年八年级第二学期期中考试英语试卷分类汇编：阅读理解
天津市和平区2018-2020年（三年）八年级第二学期期中考试英语试卷分类汇编阅读理解2019-2020学年天津市和平区八年级英语下期中区统考（线上测）试题三、阅读理解（本大题共15 小题；每小题 2 分，共30 分）阅读下面的材料，从每小题所给的A、B、C、D 四个选项中选出最佳选项。
AAn old woman was playing a good game of bridge (打桥牌) with her friends one evening. “Oh, sorry! I ha ve to go back home and make dinner for my husband! He is going to be really angry if it’s not ready on time!” she said suddenly.When she got home, she realised that she didn’t have enough time to go to the supermarket, and all she had in the cupboard was a lettuce leaf, an egg, and a can of cat food. In a hurry she opened the can, mixed in the egg, and put the lettuce leaf on it just as her husband came back.She watched nervously as her husband sat down to have his dinner. To her surprise, her husband r eally enjoyed his dinner. “My dear, this is the best dinner you have made for me in forty years of marriage. You can make this for me every day.”So every bridge night from then on, the woman made her husband the same dish. She told her bridge friends about it and they were all surprised.“You’re going to kill him!” they shouted at her. Two months later, her husband really died.The women were sitting around the table playing bridge when one of the friends said, “You killed him! We told you that feeding him that cat food every week would do him in! How can you just sit there so calmly and play bridge knowing you killed your husband?The wife calmly replied, “I didn’t kill him. He fell off a tall tree while he was trying to catch a bird.”31. The old woman liked to __________ .A. eat with her friendsB. play bridgeC. cook for her husbandD. buy food for her cat32. How did the old woman make dinner for her husband that evening?A. She mixed the cat food and an egg and put a lettuce leaf on it.B. She went shopping and bought a lot of food for dinner.C. She took him to the restaurant and ate a delicious dinner.D. She cooked the meat, egg and then put a lettuce leaf on it.33. How did her husband like the dinner?A. He was angry at it.B. He was afraid of it.C. He was strict with it.D. He was pleased with it.34. What is the reason for the old woman’s husband’s death?A. The woman killed him.B. He ate too much cat food.C. He fell off a tall tree.D. The bird killed him.35. What can we learn from the story?A. The old woman gave up playing bridge in the end.B. The old woman’s friends thought she killed her husband.C. The old woman’s husband was too bad to her.D. The old woman gave her husband cat food for forty years.BDo you yawn (打哈欠) sometimes when you are tired and sleepy? Maybe your answer is yes.Here is an interesting story. Let’s have a look at it together!One morning, Betty was not able to do her work. She felt too tired. She put down all of her books, yawned and felt much better. Betty looked up. Had the teacher seen her? To her surprise, the teacher was yawning, too. He took a deep breath and opened his mouth wide. He closed his eyes a bit and let out his breath in a big, slow yawn. Then Betty heard other yawns. The teache r said, “Betty yawned because our doors and windows are closed. And the room is warm. Her body needed more air. Maybe she yawned because she was tired. Or she just needed to move a bit. Do you feel better now, Betty?” he asked. “Yes,” said Betty. “Yawns wake us up,” the teacher said. “When you yawn, you can stretch (伸展) many parts of your body. That stretching makes you feel good.”There were more yawns in the classroom. “People do not know why they yawn,” the teacher said. “But if you see a yawn, hear one, or even read about one, you may yawn too. And once your yawn starts, you can’t stop it at all. You may close your mouth to stop it. But the yawn will still come at once.” The teacher stood up and said, “Let’s open the windows and let fresh air in. You ma yalso go out for a drink. A cold drink or water on your face helps to stop yawns. Betty may go first.”How do you feel now after you have read this story? Did you yawn? Watch a friend read this. See if your friend starts to yawn. If you see a yawn, you will know why! But if you keep yawning all the time, you must see the doctor!36. Betty yawned because ______________________.A. the teacher yawnedB. she put down her booksC. she felt too tiredD. she felt too hungry37. What was the teacher doing when Betty yawned?A. He was also yawning.B. He was watching Betty.C. He was still reading loudly.D. He was moving his body.38. When we see others yawning, what may we do then?A. We may stretch our bodies.B. We may follow them and yawn.C. We may stop them at once.D. We may help them with lessons.39. What kind of thing can help to stop yawns?A. A warm drink in your mouth.B. Red ink on the face.C. Cold clothes on the body.D. Cold water on the face.40. What can we learn from this passage?A. We shouldn’t yawn in class.B. Yawning is good for health.C. Yawning is just for students.D. It’s no use yawning at all.CHobbies are an important part of life. A great hobby will help you feel relaxed, will allow you to learn more about yourself, and will help you in developing life skills and in learning lessons that will make you live a better life. From painting to reading, there are a large number of hobbies you can take up. If you’re choosing a new hobby, the following suggestions can hel p you.When looking for a new hobby, you can think about the subjects you like to learn about, or the thing you enjoy doing. For example, if you’re a woman, you can take up hobbies like cooking, gardening, and some others. If you’re a man, you can consider hobbies like hunting, fishing, sports, etc.Are you a good writer, speaker, painter, or an expert at something else? Think hard about it bygoing over this question. You’ll certainly find your passion (激情), and this will guide you to choose a hobby that suits you.Pay attention to your talks. What do you enjoy talking about? What can you go on talking about easily? You may ask others about the topics you talk about the most. Your conversations can show a lot about your passion which can be developed into a hobby.Anyhow, picking a new hobby is a big decision, as this is an activity that you’ll spend much time and money on. But remember: It’s just a hobby. You can always consider something different if you find that the activity you chose isn’t as satisfying as you thought it would be.41. Hobbies are important because they ______________.A. make us remember a lot of thingsB. make us never feel stressedC. help us make much moneyD. help us live a better life42. According to the second paragraph, a hobby should be something that .A. brings you more moneyB. helps you study betterC. you are interested inD. makes you different from others43. Which topic can become your hobby?A. The topic you talk about with difficulty.B. The topic you often talk about.C. The topic that is easy to you.D. The topic that interests your friends.44. What does the last sentence of the passage tell us?A. Hobbies don’t fit you at timesB. Hobbies fit you all the time.C. Hobbies are in the activities.D. Hobbies are not for everyone.45. What is the passage mainly about?A. The importance of good hobbies.B. Facts about some good hobbiesC. Ways of choosing a hobby.D. Ideas about changing your hobbies.答案：31~35 BADCB 36~40 CABDB 41~45 DCBAC天津市和平区2018-2019学年八年级下学期期中学情调研英语试题四、阅读理解（本大题共15小题, 每小题1分, 共15分）阅读下面的材料, 从每小题所给的A、B、C、D四个选项中选出最佳选项AOnce a king got two nice falcons（猎鹰）from his son. He had never seen such beautiful falcons before. He loved them so much and he ordered the best falconer to train them to fly.After several months, the king came to see how the training was going on. He found that one falcon had already been able to fly high in the sky, while the other was staying on the branch（树枝）of a tree quietly, just keeping still.The king called all his falconers together and ordered them to try every way they could to make the other falcon fly. But none of them succeeded. One day, while the king was taking a walk in the forest, an idea came to his mind. Maybe someone who knew the natural environment well could solve this problem. He asked for a farmer who lived in the forest into his palace to train it at once.The next morning, the king saw the other falcon flying above in the sky freely, “it is unbelievable!” shouted the king. How could you make it happen?”The farmer replied, “ It's very easy. I just cut off the branch where the falcon rested. ”It is always the same to human beings. We all have "two flying wings" in our hearts as well, but we often seem not to notice them and stay where we just for safety and comfort. We won't realize we can fly so high and freely until the "branch" we are resting on breaks.46. What did the king do after he got the two falcons?A. He kept them on the branch of a tree.B. He sent them to a farmer in the forest.C. He set them free and let them fly in the sky.D. He made the best falconer train them to fly.47. Why did the king call all his falconers together?A. Because he wanted to get more falcons.B. Because he wanted the other falcon to fly.C. Because he wanted them to see his falcons.D. Because he wanted to know more about his falcons.48. Who finally made the other falcon fly freely in the sky?A. The king.B. The king's son.C. The farmer.D. The best falconer.49. How did the king feel when he saw the other falcon fly freely in the sky?A. Excited.B. Moved.C. Worried.D. Relaxed.50. What is the best title for the text?A. The Wise KingB. The Nice FalconsC. The Best FalconerD. The Flying Wings.BSan Francisco has its cable cars. Seattle has its Space Needle. And, Longview has its squirrel （松鼠）bridge. The bridge is now a local landmark.The Nutty Narrows Bridge was built in 1963 by a local builder, Amos Peters, to give squirrels a way to cross the busy road without being hurt by passing cars.Before the bridge was built, squirrels had to avoid traffic to and from the Park Plaza office building. Many times, Peters and other workers saw squirrels being run over.One day Peters found a dead squirrel, and that day's coffee break discussion turned into squirrel safety. The group of businessmen came up the squirrel bridge idea and named the bridge "Nutty Narrows. ”Amos Peters and Bill Hutch started to build the bridge. It cost $1, 000.It didn't take long before reports of squirrels using the bridge started. Squirrels were even seen guiding their young and teaching them the ropes. The story was picked up by the media, and Nutty Narrows became known in newspapers all over the world.In 1983, after 20 years of use, Peters took down the worn-out bridge. Repairs were made and crosspieces（横木）were replaced. The sign was repainted and in July 1983, hundreds of animal lovers attended the completion ceremony of the new bridge.Peters died in 1984, and a ten-foot wooden squirrel sculpture（雕像）was placed near the bridge in memory of its builder and his devotion（奉献）to the project.51. The Nutty Narrows Bridge was built in order to ______________.A. offer squirrels a place to eat nutsB. set up a local landmarkC. help improve trafficD. protect squirrels52. What happened over the coffee break discussion?A. A bridge was built by squirrels.B. The squirrel bridge idea was born.C. Peters named the bridge.D. A squirrel was found dead.53. What does the underlined phrase "teaching them the ropes" probably mean in the text?A. Passing them a rope.B. Directing them to store food for winter.C. Teaching them a lesson.D. Showing them how to use the bridge.54. Which of the following is TRUE of the squirrel bridge?A. It was replaced by a longer one.B. It was built from wood and metal.C. It was rebuilt after years of use.D. It was named by Peters.55. What can we learn about Amos Peters?A. He is remembered for his love of animals.B. He donated $1, 000 to build the bridge.C. He was a member of the bird family.D. He was given some money for building the bridge.CAndrew was smart when he was young. He liked doing things in a way that he thought to be clever. But sometimes he made wrong choices.One day, his father gave him ten dollars and asked him to buy some goldfish. When he got to the market, he found that the killifish（蛛鱼）looked like small goldfish, and they were much cheaper. So he bought some killifish and kept the rest of the money for himself.When he got home, his father realized what Andrew did at once. He put the fish in the tank （鱼缸）without saying anything at first. He knew his son didn't buy the right fish. At the same time, he thought his son might have an advantage in marketing （市场销售）. And he should think of a way to help his son grow well. He had an idea. Then he said to his son, “Andrew, do you know what you bought yesterday? Are they goldfish?” Andrew didn't know what to say. His father continued, °Tm glad you know how to save money. But it's not right to be dishonest. You should do things honestly, or others won't trust you. " Then he helped Andrew start with some chores, like buying daily things, helping his uncle in the store and managing his own pocket money. Later, Andrew worked as a salesman. He felt himself strong in marketing and kept working hard at it. Finally, he became a successful businessman.Several years later, when talking about the key to his success, Andrew said, “Thanks to myfather, I got to know myself well and developed in a right wa y. ”56. How much money did Andrew spend on the fish?A. Just ten dollars.B. Less than ten dollars.C. More than nine dollars.D. More than ten dollars.57. What might the underlined "chores" mean in Chinese?A. 困难B. 事业C. 琐事D. 学业58. Which of the following is the RIGHT order according to the passage?①Andrew's father saw the killifish.©Andrew became a successful businessman.③Andrew got ten dollars from his father.©Andrew helped his uncle in the store.A. ①③④②B. ③④①②C. ④①②③D. ③①④②59. Why did Andrew thank his father?A. Because his father taught him how to grow better.B. Because his father taught him how to look after himself.C. Because his father told him the importance of helping others.D. Because his father helped him find a good job.60. What can we know from the passage?A. In fact, Andrew liked killifish more than goldfish.B. Andrew's father was angry when he saw the killifish.C. Many businessmen are successful because of their great fathers.D. A smart father can help his child a lot during his/her growing up.答案：46-50 DBCAD 51-55 DBDCA 56〜60 BCDAD天津市和平区2018-2019学年八年级下学期期中学情调研英语试题四、阅读理解（本大题共15小题，41. 50题每小题2分，51. 55题每小题1分，共25分）阅读下面的短文，从每小题所给的A、B、C和D选项中选出一个最佳选项。
和平区2018-2019八年级上学期期中数学试卷(含答案)
A
E
D
B
F
C
参考答案
一、选择题: （本大题共 12 小题，每小题 3 分，共 36 分）
1．D 2．C 3．A 4．C 5．D 6．A
7．C 8．B 9．B 10．B 11．A 12．A
二、填空题: （本大题共 6 小题，每小题 3 分，共 18 分）
13．42° 14．108°
15．答案不惟一，如 AB DC ， ACB DBC 等
………………………1 分 A
ED G
F
C
∴ BAG CAG 1 BAC 45 ． 2
∴ BAG C ．
………………………2 分
∵ AE BD ， ∴ ABG BAE 90 ． ∵ CAF BAE 90 ，
∴ ABG CAF ．
………………………3 分
∵ AG CF ,
∴ AD CF ．
……………………………………8 分
①等边三角形的三个内角都相等；
②等边三角形的每一个角都等于 60°；
③三个角都相等的三角形是等边三角形；
④有一个角是 60°的等腰三角形是等边三角形．
其中，正确说法的个数是
ห้องสมุดไป่ตู้（A）1
（B）2
（C）3
（D）4
6．已知等腰三角形的一边长等于 4，一边长等于 9，则它的周长为
（A）22
（B）17
（C）17 或 22
（D）26
7．如图，△ ABC 中， AD 平分 BAC ， BE 平分 ABC ， AD ， BE 相交于点 O ，连
接 CO ，则有
A
（A）△ CEO ≌△ CDO
（B） OE OD （C） CO 平分 ACB
2018~2019学年天津和平区天津市九十中学初二下学期期中语文试卷(解析)
D. 这首诗表现了主人公对意中人执着追寻的精神以及可望不可及的绝望情绪。
【答案】 D
【解析】 D项“绝望情绪”对《蒹葭》这首诗的理解和分析不正确。《蒹葭》内容是写主人公 隔水远望，伊人正姗姗而来，仿佛就在不远处的水中陆地上，若即若离。抒发了，主 人公在岸边思念伊人却不能得的复杂心情。
7. 阅读说明文《你了解太阳吗？》，完成下列各题。 ①太阳是太阳系的中心天体，占太阳系总体质量的99．86%。太阳系中的八大行星、小行
5. 下列有关文学常识及课文内容的表述，不. 正确的一项是
A. 《社戏》是我国伟大的文学家、思想家、革命家鲁迅先生写的一篇短篇小说，表达了作者对 少年时代生活的怀念。
B. 《回延安》这首诗用陕北民歌“信天游”的形式写成，使用了富有地方色彩的词语，展示出 浓郁的陕北风情。
C. 《大自然的语言》题目运用比喻的修辞手法，不但生动、形象、贴切、风趣。而且比“简介 物候学”之类的题目更新颖、别致，富有吸引力。
（ 1 ） 解释下列句中加点词语的含义。
1 阡陌交. 通. （
）
2 悉. 如外人（
）
3 其丈夫方. 担粪灌园（
）
4 鸡犬鸣吠. （
）
（ 2 ） 用“／”标出下面句子的朗读节奏。
1 有良田美池桑竹之属。
2 余顾而慕之。
（ 3 ） 翻译下列句子。
料，坍缩成一颗白矮星。
（ 1 ） 对全文层次的划分正确的一项是
A. ①②③/④⑥⑥/⑦⑧⑨⑩
B. ①/②③④⑥⑥⑦⑧/⑨⑩
C. ①/②/③④⑥⑧⑦⑧⑨/⑩
D. ①②/③④⑥⑥⑦⑧/⑨⑩
（ 2 ） 对下面说明方法判断不正确的一项是
A. 太阳是太阳系的中心天体，占太阳系总体质量的99.86%。（列数字）
天津市和平区2018-2020年八年级第二学期期中考试英语试卷分类汇编：完形填空
天津市和平区2018-2020年（三年）八年级第二学期期中考试英语试卷分类汇编完形填空2019-2020学年天津市和平区八年级英语下期中区统考（线上测）试题二、完形填空（本大题共10 小题，每小题1 分，共10 分）阅读下面短文，掌握其大意，然后从各题所给的A、B、C、D 四个选项中选出最佳选项。
Griffing is 91 years old now, but she is working in a hospital. She has been at the same job 21 71 years. She says that being part of the medical field when she started to work at the 22 of 20 is “just magic”.The 23 and nurses regard (看作; 认为) Griffing as “the heart and soul of the hospital. Griffing was 24 at the age of 19, and lived in the hospital where she would work in the end. She 25 there for four months.One day, some doctors were complaining that a nurse didn’t come in, and that they were too busy. Griffing says that one of them asked her, “Are you a nurse? You should go to work.” Then she 26 in that hospital.Now, Griffing is the hospital’s goodwill ambassador (亲善大使). Griffing always 27 at her patients because she understands how 28 a smile in her work can be to others.It’s no wonder that Griffing has been off sick for only four days in her 71 years in the job.“I don’t have time to be upset. I refuse to be 29 . I don’t have time to be sad, because I’m having too much fun being happy. I work every day. I have to think and 30 problems every day. I will retired when they push me out of the door or c arry me out in a box,” she says.21. A. with B. on C. for D. in22. A. age B. beginning C. year D. front23. A. workers B. teachers C. actors D. doctors24. A. worried B. ill C. sad D. happy25. A. looked B. stayed C. played D. believed26. A. worked B. found C. built D. broke27. A. laughs B. chooses C. hopes D. smiles28. A. impossible B. important C. comfortable D. difficult29. A. tired B. excited C. funny D. upset30. A. cook B. decide C. solve D. delete答案：21~25 CADBB 26~30 ADBDC天津市和平区2018-2019学年八年级下学期期中学情调研英语试题三、完形填空（本大题共10小题, 每小题1分, 共10分）阅读下面短文, 掌握其大意, 然后从各题所给的A、B、C、D四个选项中选出最佳选项。
天津市和平区17—18学年下学期八年级期中考试英语试题(附答案)$865058
天津市和平区17—18学年下学期八年级期中考试英语试题本试卷分为第Ⅰ卷（选择题）、第Ⅱ卷（非选择题）两部分。
第Ⅰ卷第1页至第8页，第Ⅱ卷第9页至第10页。
试卷满分120分。
考试时间100分钟。
考试结束后，将本试卷和“答题卡”一并交回。
祝各位考生考试顺利!第I卷选择题（共65分）一、听力理解（共15分，每小题1分）A)在下列每小题内，你将听到一个句子并看到供选择的A、B、C三幅图画。
找出与你所听句子内容相匹配的图画。
1.A. B. C.2.A. B. C.3.A. B. C.4.A. B. C.B)下面你将听到五组对话，每组对话后都有一个问题。
根据对话内容，从每组所给的A、B、C三个选项中找出能回答所提问题的最佳选项。
5. What is the man doing this weekend?A. Go swimming.B. Climb the mountain.C. Go to the cinema.6. What does Mark want to borrow?A. Mobile phone.B. A dictionary.C. A computer.7.When is the man leaving?A. 7:30.B. 6:30.C. 6:00.8. What does the boy’s mother look like?A. Tall and beautiful.B. Short and beautiful.C. Tall and friendly.9. Who is going to phone Jane?A. Linda.B. Lily.C. Jenny.C)听下面长对话或独白。
每段长对话或独白后都有几个问题，从题中所给的A、B、C三个选项中选出最佳选项。
听下面一段材料，回答第10至第12题。
10. What’s the matter with Molly?A. She f eels sleepy.B. She failed the exam.C. She has a headache.11. What kind of problem are they talking about?A. Traffic.B. Noise pollution.C. School.12. What will Molly do to protect herself?A. Move away.B. Call 110.C. Write to the newspaper.听下面一段材料，回答第13至第15题。
2017-2018学年天津市和平区八年级下期中数学试卷(含答案解析)
2017-2018学年天津市和平区八年级（下）期中数学试卷一、选择题（本大题共12小题，每小题3分，共36分．在每小题给出的四个选项中，只有一项是符合题目要求的）1．下列二次根式中，是最简二次根式的是（）A．B．C．D．2．若在实数范围内有意义，则x的取值范围是（）A．x≥3B．x≤9C．x≥﹣3D．x≤﹣93．下列计算正确的是（）A．B．C．D．4．在下列由线段a，b，c的长为三边的三角形中，不能构成直角三角形的是（）A．a＝40，b＝50，c＝60B．a＝1.5，b＝2，c＝2.5C．，b＝1，D．a＝7，b＝24，c＝255．如图，点D，E，F分别是△ABC的边AB，BC，CA的中点，连接DE，EF，FD，则图中平行四边形的个数为（）A．1个B．2个C．3个D．4个6．化简的结果是（）A．B．C．D．7．如图，在Rt△ABC中，∠C＝90°，∠A＝30°，AC＝，则BC的长等于（）A．B．2C．1D．8．已知是整数，正整数n的最小值为（）A．0B．1C．6D．369．下列命题中正确的是（）A．对角线相等的四边形是平行四边形B．对角线互相垂直的平行四边形是矩形C．对角线相等的平行四边形是菱形D．对角线相等的菱形是正方形10．如图，已知△ABC，分别以A，C为圆心，BC，AB长为半径画弧，两弧在直线BC上方交于点D，连接AD，CD，则有（）A．∠ADC与∠BAD相等B．∠ADC与∠BAD互补C．∠ADC与∠ABC互补D．∠ADC与∠ABC互余11．已知a，b分别是6﹣的整数部分和小数部分，则（）A．a＝2，B．a＝3，C．a＝4，D．a＝6，12．矩形ABCD中，AB＝3，BC＝4，点E是BC边上一点，连接AE，把∠B沿AE折叠，使点B 落在点B′处，当△CEB′为直角三角形时，BE的长为（）A．3B．C．2或3D．3或二、填空题（本大题共6小题，每小题3分，共18分）13．命题“如果两个实数相等，那么它们的平方相等”的逆命题是，成立吗．14．如图，矩形ABCD的对角线AC，BD相交于点O，∠AOB＝60°，AB＝3．则矩形对角线的长等于．15．如图，菱形ABCD 中，∠B ＝60°，AB ＝4，四边形ACEF 是正方形，则EF 的长为 ．16．如图，在边长为2的菱形ABCD 中，∠A ＝60°，M 是边AD 的中点，则CM 的长＝ ．17．已知，点E 、F 、G 、H 在正方形ABCD 的边上，且AE ＝BF ＝CG ＝DH ．在点E 、F 、G 、H 处分别沿45°方向剪开（即∠BEP ＝∠CFQ ＝∠DGM ＝∠AHN ＝45°），把正方形ABCD 剪成五个部分，中间的部分是四边形PQMN ．（1）如图①，四边形PQMN 正方形（填“是”或“不是”）；（2）如图②，延长DA 、PE ，交于点R ，则S △RNH ：S 正方形ABCD ＝ ；（3）若AE ＝5cm ，则四边形PQMN 的面积是 cm 2．18．如图，在正方形网格中，每个小正方形的边长均为1，每个小正方形的顶点称为格点．请你在给出的5×5的正方形网格中，以格点为顶点，画出五个直角三角形，这五个直角三角形的斜边长分别为，，，，（画出的这五个直角三角形除顶点和边可以重合外，其余部分不能重合）．三、解答题（本大题共7小题，共46分．解答应写出文字说明、演算步骤或推理过程）19．（8分）计算：（1）；（2）．20．（6分）已知A，B，C三地的两两距离如图所示，A地在B地的正东方向，那么C地在B地的什么方向？21．（6分）如图，直角三角形纸片OAB，∠AOB＝90°，OA＝1，OB＝2，折叠该纸片，折痕与边OB交于点C，与边AB交于点D，折叠后点B与点A重合，求OC的长．22．（6分）如图，在Rt△ABC中，∠ACB＝90°，CD⊥AB于点D，∠ACD＝3∠BCD，E是斜边AB的中点．（1）∠BCD的大小＝（度）；（2）∠A的大小＝（度）；（3）求∠ECD的大小．23．（6分）如图，在▱ABCD中，点E，F分别在边BC，AD上，且AF＝CE．求证：四边形AECF。
天津市和平区2018-2020年八年级第二学期期中考试英语试卷分类汇编：单项选择
天津市和平区2018-2020年（三年）八年级第二学期期中考试英语试卷分类汇编单项选择2019-2020学年天津市和平区八年级英语下期中区统考（线上测）试题一、单项填空（本大题共20 小题，每小题 1 分，共20 分）从下列每小题所给的A、B、C、D 四个选项中，选出可以填入空白处的最佳选项。
1. To my surprise, hero in this cartoon story is ugly duck．A. a; anB. the; aC. the; anD. 不填; a2. The little boy has many toy cars and they much space of his bedroom.A. take backB. take awayC. take offD. take up3. The story The Farmer and the Snake teaches us an important : Never show pity to bad people.A. surpriseB. jokeC. lessonD. report4. My grandmother dinner when I got home yesterday.A. was cookingB. will cookC. has cookedD. cooks5. —What are you going to do this weekend?—I yet.A. won’t decideB. haven’t decidedC. have decidedD. didn’t decide6. Last Sunday was Andy’s birthday. We had a birthday party.A. twelveB. the twelfthC. twelfthD. the twelve7. —Hello, may I speak to Mr.Wang?—Oh, sorry! He to Beijing. He will come back in two days.A. goesB. has beenC. wentD. has gone8. Hurry up! The match for ten minutes.A. has been onB. has beganC. has begunD. began9. The teacher encouraged the children loudly in front of the people.A. spokeB. to speakC. speakingD. speak10. Mary is an student. She answers the teachers’ questions in class.A. active; activeB. actively; activeC. active; activelyD. actively; actively11. —I’m sorry I my exercise book at home this morning．—It doesn’t matter. Don't forget it here this afternoon．A. left; to bringB. forgot; bringingC. left; to takeD. forgot; to bring12. —W hat’s th e matter your brother?—He has a cold.A. onB. atC. withD. for13. Today I will meet my best friend. We each other since I left school.A. don’t seeB. haven’t seenC. won’t seeD. didn’t see14. Let’s enjoy the song You Are My Sunshine. It sounds .A. badB. badlyC. beautifullyD. beautiful15. My cousin is heavy because he often eats fast food.A. much too; too muchB. too much; too muchC. much too; too manyD. too much; too many16. The boy has learned English .A. for five yearsB. for five years agoC. since five yearsD. five years ago17. I Shanghai twice. I there last summer and this winter.A. have been to; have gone toB. have been to; will goC. have gone to; wentD. have been to; went18. —Mom, I got a big box from express(快递).What is it？—I’m not sure. It be a present from your grandmother．A. mustB. willC. mightD. can19. —?—He is naughty but friendly.A. What does your brother likeB. What is your brother likeC. What does your brother look likeD. How does your brother like it20. —It's kind of you to help me carry the heavy box.—____________________.A. Have a tryB. Not reallyC. It’s my pleasureD. It doesn’t matter答案：1~5 CDCAB 6~10 CDABC 11~15 ACBDA 16~20 ADCBC天津市和平区2018-2019学年八年级下学期期中学情调研英语试题二、单项填空（本大题共15小题, 每小题1分, 共15分）从下列每小题所给的A、B、C、D四个选项中, 选出可以填入空白处的最佳选项。
2018年天津市和平区八年级下数学期中复习试卷有答案
2018年八年级数学期中复习试卷一、选择题:1.函数y=自变量的取值范围是（）A．x≠﹣3 B．x＞﹣3 C．x≥﹣3 D．x≤﹣32.下列计算正确的是( )A．(3a)2=6a2B．(-3)-2=6 C=-2 D=3.若三边长满足，则是( ) A．等腰三角形B．等边三角形C．直角三角形D．等腰直角三角形4.如图,在平行四边形ABCD中,∠BAD的平分线交BC于点E,∠ABC的平分线交AD于点F,若BF=12,AB=10,则AE的长为（）A．13 B．14 C．15 D．165.下列计算正确的是（）A．B．C．D．6.如图，在菱形ABCD中，E，F分别在AB，CD上，且BE=DF，EF与BD相交于点O，连结AO．若∠CBD=35°，则∠DAO的度数为（）A．35°B．55°C．65°D．75°7.若一个三角形的三边长分别为6、8、10，则这个三角形最长边上的中线长为（）A．3.6 B．4 C．4.8 D．58.如图,将一个矩形纸片ABCD，沿着BE折叠，使C、D点分别落在点C，D1处．若∠C1BA=50°，则1∠ABE的度数为（）A．15°B．20°C．25°D．30°9.下列命题中,真命题是（）A．对角线相等的四边形是矩形 B.对角线互相垂直的四边形是菱形C.对角线互相平分的四边形是平行四边形D.对角线互相垂直平分的四边形是正方形10.如图，已知菱形OABC的顶点O（0，0），B（2，2），若菱形绕点O逆时针旋转，每秒旋转45°，则第60秒时，菱形的对角线交点D的坐标为( )A．(1，-1) B．(-1，-1) C．(2，0) D．(0，-2)二、填空题:11.点Q（5，﹣12）到原点的距离是．12.函数y=的自变量的取值范围是13.如图，在Rt△ABC中，∠ACB=90°，点D、E、F分别是AB、AC、BC中点，若CD=5，则EF长为.14..E为□ABCD边AD上一点，将ABE沿BE翻折得到FBE，点F在BD上,且EF=DF．若∠C=52°，则∠ABE=______15.如图，矩形ABCD的对角线AC，BD相交于点O，分别过点C，D作BD，AC的平行线，相交于点E．若AD=6，则点E到AB的距离是________．16.如图，在等边△ABC中，AB=6，N为线段AB上的任意一点，∠BAC的平分线交BC于点D，M是AD上的动点，连结BM、MN，则BM+MN的最小值是 .三、解答题:17.计算：18.计算：19.如图，已知在△ABC中，D是BC的中点，DE⊥BC，垂足为D，交AB于点E，且BE2﹣EA2=AC2，①求证：∠A=90°．②若DE=3，BD=4，求AE的长．20.如图,四边形ABCD中,AD∥BC,AE⊥AD交BD于点E,CF⊥BC交BD于点F,且AE=CF．求证：四边形ABCD是平行四边形．21.如图所示,在菱形ABCD中,AB=2,∠DAB=60°,点E是AD边的中点,点M是AB边上一动点(不与点A重合),延长ME交射线CD于点N,连接MD,AN.(1)求证:四边形AMDN是平行四边形;(2)①当AM为何值时,四边形AMDN是矩形?②当AM为何值时,四边形AMDN是菱形?22.已知E,F分别为正方形ABCD的边BC,CD上的点,AF,DE相交于点G,当E,F分别为边BC,CD的中点时,有AF=DE,AF⊥DE成立.试探究下列问题:(1)如图①,若点E不是边BC的中点,F不是边CD的中点,且CE=DF,上述结论是否仍然成立?(请直接回答“成立”或“不成立”,不需要证明)(2)如图②,若点E,F分别在CB的延长线和DC的延长线上,且CE=DF,此时,上述结论是否仍然成立?若成立,请写出证明过程,若不成立,请说明理由;(3)如图③,在(2)的基础上,连接AE和EF,若点M,N,P,Q分别为AE,EF,FD,AD的中点,请判断四边形MNPQ是“矩形、菱形、正方形”中的哪一种,并证明你的结论.参考答案1.B.2.D.3.C4.A5.B．6.D.7.B8.B.9.A.10.B.11.答案为：13．12.答案为：≥﹣3且x≠﹣1 ．13.答案为：514.答案为：5115.答案为：916.答案为：;17.解：原式=0；18.解：原式=919.（1）证明：连接CE，如图，∵D是BC的中点，DE⊥BC，∴CE=BE…（2分）∵BE2﹣EA2=AC2，∴CE2﹣EA2=AC2，∴EA2+AC2=CE2，∴△ACE是直角三角形，即∠A=90°；（2）解：∵DE=3，BD=4，∴BE==5=CE，∴AC2=EC2﹣AE2=25﹣EA2，∵BC=2BD=8，∴在Rt△BAC中由勾股定理可得：BC2﹣BA2=64﹣（5+EA）2=AC2，∴64﹣（5+AE）2=25﹣EA2，解得AE=1.4．20.证明：∵AE⊥AD，CF⊥BC，∴∠EAD=∠FCB=90°，∵AD∥BC，∴∠ADE=∠CBF，在Rt△AED和Rt△CFB中，∵，∴Rt△AED≌Rt△CFB（AAS），∴AD=BC，∴四边形MNPQ是正方形。
2017_2018学年天津和平区初二上学期期中语文试卷及详解(PDF版)
2017~2018学年天津和平区初二上学期期中语文试卷A.B.C.D.下列加粗字注音完全正确的一项是溃退（kuì） 浩瀚（hàn ） 黝黑（yǒu ） 炽热（chì）要塞（sài ） 镌刻（juān ） 滞留（zhì） 教诲（huǐ）颁发（bān ） 畸形（qí） 骤雨（zhòu ） 胆怯（qiè）翘首（qiào ） 不辍（chuò） 匿名（nì） 绯红（fēi ）1 A.光芒 一碧万顷 心曲 怀抱B.辉煌 一泻千里 心扉 怀抱C.光芒 一往无前 心扉 情怀D.辉煌 一望无际 心曲 情怀根据语境在空格处填上恰当的词语，完全正确的一项是每一条河流都是一曲古老的赞歌，唱出了远古文明的 ，从未看过翻滚的巨浪的人，难以想象万马奔腾、 的壮丽景象。
让我们迈开脚步，打开 ，投入大自然的 。
2 A.B.C.D.下面句子没有语病的一项是央视《朗读者》得到观众的广泛好评，是因为其节目形式新颖、文化内涵丰富的缘故。
据统计，2017年一季度，国内汽油行业销售量与去年同期相比，增加大约12．7%左右。
市卫生监督部门加大了对市场上牛肉的抽样检测，防止不合格肉制品重现百姓餐桌。
为了推动儿童文学的发展和繁荣，首届“曹文轩儿童文学奖”征稿活动，目前全面启动。
3 A.B.C.D.下列句子的标点符号使用不正确的一项是“好吧。
”他说，“我相信你能行！”我国南海蕴藏着丰富的海洋动力资源，如潮汐能、波能等……给成功者一个微笑，那是赞赏；给失败者一个微笑，那是鼓励。
在挫折和磨难面前，你是做畏缩逃避的懦夫，还是做奋起搏击的勇士？4下列句子顺序排列最恰当的一项是①竹，柔韧清秀，刚健挺拔，最宜入诗入画。
②竹如谦谦君子，它有兰的优雅，松的高洁，深受古代文人的青睐。
5一、选择题（14分）A.④⑤②①③B.①③②⑤④C.①②③⑤④D.①③④②⑤③那成片的竹林，风过如丝弦裂帛，雨来如琴瑟和鸣，那就是一首抒情诗，一幅水墨画。
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b. 选取合适的温度计
c. 待温度计示数稳定后再读数，读数时温度计要继续留在被测液体中
d. 估计被测液体的温度
19. 有一根长为 L 的钢管，当在一端打击一下时，某人在它的另一端听到两次响
声，时间间隔为△t。先听到的那次响声是从 传来的；若声音在空气中的速
度为v气，则声音在钢中的速度v钢=
。
4
八年级上册
A. “长征七号”
B. “天宫二号”
C. 文昌航天发射场
D. 地球
图1
3. 小纸片会在发声的扬声器的纸盒上跳动，发声的音叉接触水面时会激起水花，
风吹树叶哗哗响， 树叶在振动。这些现象说明了（ ）
A．声音是由物体振动产生的
B．声音能在水中传播
C．声音的传播需要介质
D．声音能在空气中传播
4. 在公共场所“轻声”说话，在课堂上“大声”回答问题，这里的“轻声”和
是小车到达 A、B 两处时，电子时钟所显示的两个不同的时刻，则：
(1)由图可知，斜面上的刻度尺的分度值为
。
(2)该实验原理是
。
(3)在实验中，为了方便计时，应使斜面的倾角适当 （选填“大”或“小”）
一些。
(4)设计实验表格，并将由图获得的实验数据填入表格。
图 10
5
八年级上册
期中考试
22．（6 分）十一国庆期间，小明家要来客人，妈妈叫小明提前从冰箱冷冻室里把
铜 铁金
质的熔点（凝固点）
、沸点（℃） 物质
熔点（凝固点）
0 ﹣117 ﹣30 113.6 1083 1535 1064
沸点
100 78.5 150 184.25 2360 2750 2500
（1）结合你的探究经历，描述小红观察到的实验现象。
（2）交流评估时，小明查阅了部分物质的熔点、沸点（见表），他发现碘的熔
B．零下摄氏141度
C．负141摄氏度
D．摄氏负141度
8. 图 4 中水的凝固图象是（ ）
图4
9. 小时同学做了一个实验：将碾碎的卫生球粉末和小树枝放入封闭的烧瓶中， 然后在酒精灯上微微加热烧瓶，发现卫生球的粉末越来越少，停止加热后，一 会儿烧瓶内的树枝上出现了洁白、玲珑剔透的人造“雪景”，对以上实验现象， 下列说法中正确的是（ ） A. “雪景”是卫生球升华而成的 B. “雪景”是卫生球凝华而成的 C. “雪景”的形成经历了汽化和液化两个物态变化过程 D. “雪景”的形成经历了升华和凝华两个物态变化过程 10. 下列几种估测最符合实际情况的是（ ） A．人步行的速度约为 5m/s B．一张试卷的厚度大约 1mm C．课桌的高度约为 1.5m D．全新的 2B 铅笔长约 18cm
，我们
（选填“能”或“不
能”)听到该频率的声音。
17. 如图 8，晓彤将一只点燃的蜡烛放在音响前，加大音量，可以观察到的现象
是
； 该现象说明
。
图8
18. 如图 9 所示，温度计的示数是
，在使用温度计测量液体的
温度时，有以下几个步骤， 请按照正确的顺序，把下列步骤重新排列：（只需
填写序号）。
图9
a. 把温度计的玻璃泡全部浸入被测液体，不碰到容器的底和壁
（选填“顺时针”、“逆时针”或“顺时针逆时针都有”）。通 过今后的物理学习，你就会明白其中的道理。
图6 3
八年级上册
15. 如图7甲所示是小明用刻度尺测量物体的长度是
表示数为
。
期中考试
；如图7乙所示的停
图7
16. 某种昆虫靠翅膀的振动而发声。如果这种昆虫的翅膀在 2s 时间内共振动
了 600 次，则它翅膀振动的频率是
1
八年级上册
期中考试
6. 如图3所示，纺纱工人工作时戴着防噪声的耳罩，这是为了（ ）
图3
A. 防止噪声产生
B. 监测噪声强弱
C. 防止噪声进入耳朵
D. 减小噪声传播速度
7. 我国的低温超导科技研究居世界领先地位，1989 年实验得到的最高转变温
度已达到－141℃， 这个温度读作（ ）
A．零下141度
B．晓军骑车的速度是 6m/s
C．晓军步行的速度是 72m/s
D．晓军从家到万达广场全程的平均速度是 2m/s
图5
第 Ⅱ 卷 非选择题（共 2 大题 共 61 分）
三、填空题（本大题共 6 小题，每小题 4 分，共 24 分）
14．要想学好物理就要养成时刻观察生活的好习惯。生活中有很多现象“司空 见惯”，如果不留心就会“视而不见”。例如，如图 6 所示，冰棍“冒”出的 “白气”，是向 （选填“上”或“下”）飘的；家中洗手盆、洗菜盆或浴 缸中装有大量的水，打开底部塞子，水从圆形下水口流出时，都会形成一个小漩 涡，每次我们都是看着水流走的，那么你是否注意到这个漩涡的旋转方向是
点是113.6℃，碘的沸点是184.25 ℃，酒精灯的火焰温度约400 ℃，他认为小
红所做的实验中，碘可能经历了由固态到液态再到气态的变化过程，小红的实
验并不能得出碘升华的结论，请你针对小明的质疑，选用上述器材或补充必要
的辅助器材设计一个实验，证明碘直接从固态变为气态，写出实验方案并扼要
说明。
7
八年级上册
八年级上册
2018 秋初二和平区期中考试
期中考试
第 Ⅰ 卷 选择题（共 2 大题 共 39 分）
一、 单项选择题（本大题共10 小题，每小题3 分，共30 分）每小题给出的四个选项中，只有一
个最符合题意，请将你选择的答案涂在答题卡相应的位置。
1. 晓燕在学校春季运动会百米赛跑中以16s的成绩获得冠军，测得她在50m处的
2
八年级上册
期中考试
二、多项选择题（本大题共 3 小题，每小题 3 分，共 9 分）每小题给出的四个选项中，
均有多个符合题意，全部选对的得 3 分，选对但不全的得 1 分，不选或选错的得零分。请将
你选择的答案涂在答题卡相应的位置。
11. 婴儿从呱呱坠地的那时起，就无时无刻不与声打交道。下列关于声的说法，
速度是6m/s，到终点时的速度为7.5m/s，则全程内的平均速度是（ ）
A．6m/s B．6.25m/s C．6.75m/s D．7.5m/s
2. 2017 年 4 月，货运飞船“天舟一号”在文昌航天发射场使用“长征七号”
运载火箭发射，并与“天宫二号”顺利完成自动交会对接，如图 1 所示，对接
完成后，若认为“天舟一号”处于静止状态，则选取的参照物是（ ）
B. “岚雾今朝重，江山此地深”雾的形成是液化现象
C. “青青园中葵，朝露待日晞”露的形成是汽化现象
D. “月落乌啼霜满天，江枫渔火对愁眠”霜的形成是凝华现象
13. 晓军从家中出发到万达广场，其中一半路程骑自行车，一半路程步行，路程
与时间图象如图5所示。则以下说法正确的是（ ）
A．晓军骑车的是图中 OA段
期中考试
四、综合题（本大题共 6 小题，共 37 分）解题中要求有必要的分析和说明，计算题还
要有公式及数据代入过程，结果要有数值和单位．
20．（6 分）步行不仅是一种简易的健身运动，而且还能方便地对一些长度进行
估测。
(1)人正常步行时，步距变化不大，因此，步距可作为身体上的一把“尺子”。
为了使这把“尺子”更可靠，请你说出一种测量步距的方法。
“大声”是指声音的（ ）
A．音调 B．响度 C．音色 D．声速
5. 如图2所示，将甲、乙两音叉发出的声音信号输入到示波器上，得到甲、乙
两种波形,从波形上可以得出（ ）
图2
A. 甲、乙两种声音的音调相同 B. 甲、乙两种声音的响度相同 C. 乙声音的音调高于甲声音的音调 D. 甲声音的响度高于乙声音的响度
期中考试
25．（7分）马路宽为D，一辆长为l1、宽为d的汽车以速度v1在路中间匀速向前
行驶，此时距车头s处有一辆长为l2的自行车要横穿马路，如图13所示，则自行
车为了安全通过马路，它行驶的速度应在什么范围？
（温馨提示：推导计算过程中需要的物理量请提前设定）
8
(2)小华测出自己的步距为 0.5 m，他从教学楼的一端走到另一端，共走了 84 步，
则教学楼的长度是多少？如果这个过程用时 35 s，则他的步行速度是多少？
21．（6 分）如图 10 所示，是某同学设计的测量小车在固定斜面上度的斜面顶端由静止自由下滑，图中的圆圈
肉拿出来。小明将肉取出发现表面有一层“白粉”，放在桌子上就去玩了，过了一会
儿他经过桌边，发现肉上“白粉”不见了，有了许多水珠。
(1)请用所学知识解释肉上“白粉”、水珠是怎么出现的？
(2)小明通过查阅说明书，冰箱的制冷剂是 R600a。请你从物态变化的角度简要叙
述它是怎么把冰箱内的热量带到冰箱外面的？
。
(3)点燃酒精灯，待水温升至 90℃时，小明同学每隔 l min 读出一次温度计示数，
小华同学及时记录在以下表格内，如此持续 8 min 后停止了读数．
t／min
012345678
温度 t 温／℃ 90 92 94 96 98 98 98 98 98
(4)请根据表格中数据，在图 11 丙的坐标系中画出水在沸腾前后温度随时间变
正确的是（ ）
A. 我们能听到远处的雷声，说明空气可以传声
B. 人在岸上大声说话也能惊动水中的鱼，说明水能传声
C. 声音在软木中传播速度比在水中慢
D. 宇航员在太空中不能直接对话，说明真空不能传声
12. 中央电视台播出的《中国诗词大会》深受观众喜爱，下列对古诗词中涉及的
热现象解释正确的是（ ）
A. “千里冰封，万里雪飘”冰的形成是升华现象
化的图线．
(5)该次实验时，水的沸点为
，说明该地的气压
（选填“等于”、
“小于”或“大于”）标准大气压。