红霉素静滴时为防止出现血栓性静脉炎,药物浓度不宜超过()。
A.3mg/ml
B.5mg/ml
C.1mg/ml
D.0.5mg/ml
E.10mg/ml
参考答案:C
Koalas sleep the day and night they get up and eat leaves. [ ]
A in;in
B. at;in
C. at; at
D. during; at
不锈钢管坡口宜采用()等制出。
A.机械切割机
B.等离子切割机
C.砂轮机
D.碳弧气割