题目

The high speed train     Qingdao and Beijing travels faster now. The train ride takes only about three hours. A. from                B. among               C. in                  D. between 答案：D 【解析】句意：青岛到北京的高速列车现在开得更快了。乘坐火车只需要三个小时。A. from从……起，来自；B. among在（其）中，……之一；C. in在……里；D. between在两者之间。between…and…，在两者之间，可以连接两个并列的成分，故答案为D。化简sin(α-π2)cos(3π2+α)tan(π-α)tan(-π-α)sin(-π-α)=-cosα-cosα．