单项选择题
A.45B.36C.18D.15
A.23B.5C.6D.9
A.240B.180C.120D.80
A.80B.160C.200D.210
A.5880种B.2940种C.1960种D.490种
A.90%B.81%C.70%D.68%
A.1200B.3600C.4800D.7200
A.12种B.5种C.9种D.7种
A.10B.12C.6D.8
A.72B.75C.78D.81
A.52B.64C.72D.74