慢性毒性试验选用大鼠体重为()
A.18~24g
B.30~50g
C.50~70g
D.80~100g
E.180~240g
参考答案:C
_____ to sunlight for too much time will do harm to one’s skin.
A.Exposed
B.having exposed
C.Being exposed
D.After being exposed
当终聚釜停止进料后,现场应密切注意终聚釜搅拌,发现振动增大应立即停止搅拌。()