臭氧样品的采集、运输及存放过程中应严格避光；样品于室温暗处存放至少可稳定（）d。
参考答案：3
进口压缩机有（）个曲拐。
Today the world is paying much more attention to,obviously, China says
and does.
A．that
B．which
C．what
D．how
