尼龙在常温下可溶于()。
A.丙酮
B.四氯化碳
C.甲酸
D.苯
参考答案:C
具有输血指征需符合以下标准()
A.急性失血血红蛋白需下降20g/L
B.慢性贫血血红蛋白低于80g/L
C.急性失血血容量减少大于20%
D.慢性失血血容量减少大于20%
E.慢性失血患者感觉头昏明显时
—You look rather tired. _______stop to take a rest?
—All right. But I’ll have to work for a few more minutes.
A.Why not
B.Why don’t
C.What about
D.How about