题目

Does this meal cost $50? I __________ something far better than this! A. prefer       B. expect       C. suggest        D. suppose 答案：B（2013•宝安区一模）规定一种运算：.abcd.=ad-bc，例如：.x215.=8，运算得：5x-2=8，x=2；按照这种运算的规定，求.x2x2x.=5中x的值为-5或1．-5或1．．