(a)(i) 从文章中就可以找到答案。Carbon footprint is the amount of carbon dioxide and other carbon compounds released by various human activities.
(ii) 文章第一段同样可以找到答案。The heaters use electricity generated by burning fossil fuels，releasing carbon dioxide and compounds, which increases the carbon footprint.
(iii)切实可行的方案才可以，比如solar energy等renewable energy, 或者采用recover, reuse等 cogeneration system循环利用产生的热量，节约能源。
(b) 考察绿色屋顶的好处，尤其注意是环境方面的好处。比如 reduce carbon dioxide by photosynthesis, lower the temperature , absorb rainfall and reduce runoff 等。
(c) 可以从agriculture的角度出发比如food 的种类、来源等。
First, they can use local food, which lessens the amount of transportation, because transportation is a major source of environmental pollution.
Second, the food service could have a meat-free day to reduce the consumption of meat. Because livestock 比vegetation消耗的资源更多，更容易造成环境污染比如animal manure.
(d) 考察native species 的优势，此题没有限制，就可以从环境、经济等多角度回答。
Native plants are more adopted to local temperature and precipitation, they can use the local natural resource completely and grow well.
Also, native plants usually have a good and stable relationship with other species, using native plants could eliminating the possibility of competition posed by introduced plants and maintain a balanced ecosystem.
(e) 考察synthetic fibers 的环境问题，比如VOCs等化学物质的释放、难降解等。
Using flooring made of plant material could reduce the amount of VOCs released by carpet.
必考的计算题目，此题比较简单，借助wind energy等alternative energy考察计算，读懂题目，理清关系，认真计算即可。
(a) An offshore wind project could not produce atmospheric pollutants, such as carbon and sulfur dioxide.
(b) An offshore wind project could drive the price of electricity down. Because 增加电力的供应，没有环境污染所产生的external cost等。
(c) 海洋所提供的能源，典型的就是tidal energy。The turbines spin as the tide flows over them and turbine is connected to a generator that produces electricity.
(iii) Arctic cod 或者Ringed seal 都可
The direction of arrows indicates the transition of energy.
(c)从题目所给的信息出发：冰川熔化，北极熊的栖息地变少，同时北极出现无冰期，缩短北极熊的捕猎时间。 The habitat of polar bear would be destroyed as the amount of sea ice has decreased. Also, hunting season for polar bear could be shortened as Arctic Ocean is now completely free of sea ice for several weeks each summer.
(d)The green house gases trapped in sea ice would be released, such as carbon dioxide and methane. These gases could absorb more infrared radiation and warm the Earth’s surface.
(ii)注意不能回答whaling，要从人类活动的商业角度分析whales死亡的原因。Overharvesting sea fishes, because it would reduce the food resource for right whales.
(iii) 要结合上一问来回答。控制fishing quantity、设置休渔期fishing moratorium.
(a)(i) carbon dioxide ,sulfur dioxide
(b)考察biomass燃烧产生的污染物质的处理方法。We can use scrubbers and electrostatic precipitators. Smokestacks fitted with scrubbers could remove particulate matters, these particles are light enough to be carried on air currents, and when humans breathe them in, the particles act as irritants.
(c) Children have underdeveloped immune and nervous systems, they are susceptible to disease caused by indoor pollutants.
(d)(i) Asbestos come from building materials, such as ceiling and floor tiles.Radon is a gas that’s emitted by uranium as it undergoes radioactive decay. It seeps up through rocks and soil and enters buildings.
(ii) To reduce asbestos, we can use flooring made of plant material instead of asbestos products.
Radon can be reduced by ventilating the basement. Because 通风换气可以降低室内有毒气体的含量，减少对人体的污染。