题目

计算：(－2x2y3)2÷＝________． 答案：【答案】－8xy5【解析】根据有理数运算规则，应该先乘方，再算除法。同底幂相除，底数不变，指数相减。解：原式＝4÷＝－8xy5.No one can tell how many sufferings the kidnapped boy ________ when he was rescued yesterday.A．hadB．has hadC．had hadD．would have