题目

A:         do you go to school? B：I take a taxi. A.When              B.Where  C.How                   D.What time 答案：C3．（1）计算：$3\frac{3}{7}-（{-1\frac{4}{21}}）$；（2）计算：${（{-1\frac{1}{2}}）^3}×（{-\frac{1}{3}}）÷\frac{3}{4}$．