主回路与控制回路对地绝缘电阻应不小于()兆欧。
A.0.5
B.1
C.1.5
D.2
参考答案:A
Mr. Smith is quite generous and warm-hearted, a person______ you can turn when having trouble.
A.for whom
B.with whom
C.to whom
D.of whom
混凝土外加剂匀质性试验测定水泥砂浆工作性,试件的砂用量为()
A、1350g
B、1500g
C、1450g
D、1400g