25. There should be a greater use of gasohol. Gasohol is a mixture of alcohol and gasoline, and has a higher octane rating and fewer carbon monoxide emissions than straight gasoline. Burning gasohol adds no more carbon dioxide to the atmosphere than plants remove by photosynthesis. Each of the following, if true, strengthens the argument above EXCEPT: (A) Cars run less well on gasoline than they do on gasohol. (B) Since less gasoline is needed with the use of gasohol, an energy shortage is less likely. (C) Cars burn on the average slightly more gasohol per kilometer than they do gasoline. (D) Gasohol is cheaper to produce and hence costs less at the pump than gasoline. (E) Burning gasoline adds more carbon dioxide to the atmosphere than plants can remove. 答案是C C的确是不对的,但我不明白的是为什么E是对的? 看解释说"E: 燃烧gasoline产生的二氧化碳比植物能消化的多,而argument中说gasohol产生的二氧化碳不比植物光合作用时能移除的多,所以优势显而易见". 根据我自己的理解就是:植物光合作用时移除的二氧化碳>gasolho产生的二氧化碳>植物能消化的二氧化碳.实在不明白优势在哪里? 希望大家能帮我解释一下.谢谢 |