中药变质的环境因素包括
A．温度
B．湿度
C．空气
D．日光
E．霉菌和害虫
参考答案：A,B,C,D,E
It is strange that the small boy _________ work out such a difficult exercise, which is even hard to settle for adults.
A．should
B．might
C．could
D．would
随机误差具备的特性有（）
A.小误差的密集性
B.同性质误差的累积性
C.大误差的有界性
D.正负误差的对称性
