5本不同的书,全部分给四个学生,每个学生至少1本,不同分法的种数为 [ ]
A.480
B.240
C.120
D.96
答案:B
A和B是互质数,但A和B不一定都是质数.______.
—Are you _____ , Daming?
—No, I'm from China. [ ]
A. English
B. England
C. an English
D. the England