平屋顶卷材防水屋面的组成中最上面一层为（）。
A．找平层
B．防潮层
C．隔离层
D．保护层
参考答案：D
是否提倡学校鼓励学生自愿参加保险？
He asked__________for a violin.
A．did I pay how much
B．I paid how much
C．how much did I pay
D．how much I paid
