Questions 3 and 4 will be based on thefollowing news item.
A.It costs less money.
B.It can be found in lakes.
C.It is more efficient.
D.It is poisonous as well.
News Item Two
Solar cells convert energy from the sun intoelectricity. (3) The researchers have replaced a toxiccompound, used to make one type of solar cell,with a chemical that is much cheaper, completely safeand works just as well. The new compound is usedto make tofu and is found in bath salts. It's also found in sea water, and so costs much lessthan the poisonous chemical currently used. Dr. Jon Major, who led the research at LiverpoolUniversity, believes that "this process could really make the difference into making itcompetitive with fossil fuels." More work will need to be done to see if the cost savings foundin the lab can work on an industrial scale. But the cost of solar energy has been steadily falling. (4) And many involved in research in the field believe that it's just a matter of time before itbecomes cheaper than coal, gas and oil, and one day replaces fossil fuels entirely.
3.What's the advantage of the new chemical according to the news?
4.How many fossil fuels have been mentioned in this news?
【小题3】本题询问新采用的化合物的优势。新闻开头提到The researchers have replaced a toxic compound,used to make one type of solar cell, with a chemical that is much cheaper, completely safe andworks just as well.指出科学家采用了一种新的化合物，这种化合物比之前采用的更低廉，同时它也是绝对安全的，所起的作用也是一样的，因而 A项表述符合新闻内容，故选 A。
【小题4】该题考查新闻中提及的化石燃料的数量。新闻末尾处提到...it's just a matter of time before itbecomes cheaper than coal, gas and oil, and one day replaces fossil fuels entirely，很显然，提到了煤炭、天然气和石油三种化石燃料，故选 C。