题目

(本小题满分8分)   已知直四棱柱的底面是边长为a的正方形， 高为, 体积为V, 表面积等于S.(1) 当a = 2, h = 3时，分别求V和S；(2) 当V = 12，S = 32时，求的值.  答案： （1）32（2）解析:(1) 当a = 2, h = 3时，V =  a2h= 12 ;       S = 2a2+ 4ah =32   .                                ---4分(2) ∵a2h= 12,  2a(a + 2h) =32，   ∴ , (a + 2h) =,∴===.                            ---4分  Though she began her ________ by singing in a local pop group, she is now a famous Hollywood movie star． [　　] A．employment B．career C．occupation D．profession