胰头癌有明显黄疸患者术前必须补充的维生素是
A．维生素A
B．维生素B
C．维生素C
D．维生素D
E．维生素K
参考答案：E
--Guess what I want to be when I grow up.
--I think you want to be a(n) _____ . You love beautiful things, right?
A．engineer
B．artist
C．nurse
D．waiter
高斯-克吕格投影（等角横切椭圆柱投影）
