气化炉建立蒸汽放空前要先对管线进行（）。
A.氮气置换
B.预热
C.排凝
D.升压
参考答案：B, C
—Let’s go to the fashion show this afternoon, shall we? — I _________ it. It’s very interesting.
A．have seen
B．am seeing
C．saw
D．had seen
如果被审计单位固有风险和控制风险水平较低，则注册会计师可选择资产负债表日后适当日期为截止日实施函证。( )
