题目

------ Tom looks very happy. He_______ have passed the exam    ------ I think so. It’s too easy after all. A. could           B. should        C. might        D. must 答案：D 用1，2，3，4，5这五个数字组成无重复数字的五位数中，恰有一个奇数在两个偶数之间的五位数有 [　　] A．12个 B．28个 C．36个 D．48个