测定有害气体的采样器放置高度应为（）
A.5米
B.3～5米
C.3米
D.1.5～3米
E.1.5米
参考答案：E
—When and where to spend the holiday ____ yet.
—Let’s make it now.
A．is decided
B．doesn’t decide
C．has not been decided
D．has decided
丧失按时限可分为暂时性丧失和__________。
