2020美赛E题

对E题的理解：
目标一：建模分析一次性塑料垃圾的最大产量
Develop a model to estimate the maximum levels of single-use or
disposable plastic product waste （定语从句修饰waste）that can safely be mitigated without further environmental damage. 在可以安全分解的前提下，分析一次性塑料垃圾的最大产量。

You may need to consider,
among many factors, （要考虑下面几个因子）the source of this waste, the extent of the current waste problem, and the availability of resources to process the waste.
目标二：讨论减少多少塑料废物可以达到环境安全的目标
This may involve considering factors impacting the levels of plastic
waste to include, but not limited to（包括但不限于下面这些因素）,
sources and uses of single-use or disposable plastics, the availability of
alternatives to plastics, the impact on the lives of citizens, or policies of
cities, regions, countries, and continents to decrease single-use or
disposable plastic and the effectiveness of such policies.
目标三：用1、2的结论确定一个一次性塑料最低水平的目标，分析影响。

（我认为这部分以分析吹水为主）
目标四：塑料问题的起因和结果在世界不同地区存在差异，探究公平性的问题，给出建议
目标五：给出目标和时间线，写两页纸大白话，考虑any circumstances that may accelerate or hinder the achievement of your target and timeline.
（突发事件这里可能用到建模）
The detail can be described by equation \eqref{eq:heat}:
\begin{equation}\label{eq:heat}
\frac{\partial u}{\partial t} - a^2 \left( \frac{\partial^2 u}{\partial x^2} + \frac{\partial^2 u}{\partial y^2} +
\frac{\partial^2 u}{\partial z^2} \right) = f(x, y, z, t)
\end{equation}。