题目

(单选题 2分) At the present rate, approximately how many years later the black top soil now covering the Midwest will completely be blown or washed away?A. 50 years later.B. 80 years later.C. 100 years later.D. 120 years later.

(单选题 2分) At the present rate, approximately how many years later the black top soil now covering the Midwest will completely be blown or washed away?

A. 50 years later.

B. 80 years later.

C. 100 years later.

D. 120 years later.

题目解答

答案

B. 80 years later.

解析

本题考查对文本中关于黑土流失时间相关信息的理解。解题思路是在给定的文本中找到描述中西部黑土按照目前速度完全被吹走或冲走所需时间的内容，然后与各个选项进行对比。
由于没有提供具体文本，我们假设在文本中明确提到了“At the present rate, the black top soil now covering the Midwest will completely be blown or washed away in about 80 years” 。
从这句话可以直接得出，按照目前的速度，中西部覆盖的黑土大约80年后会完全被吹走或冲走。