一天中，相对湿度的最小值出现在（）。
A.清晨
B.14～15h
C.傍晚
参考答案：A
I really don't know _____ I had my money stolen. [ ]
A. when was it that
B. that it was when
C. where it was that
D. it was where that
机采白细胞献血员的血细胞的比容应（）。
A.≥0.28
B.≥0.30
C.≥0.33
D.≥0.35
E.≥0.38
