水力除尘水压应保持在不小于（）
A.1.0kg/cm2
B.2.0kg/cm2
C.3.0kg/cm2
参考答案：B
I _____ there little more than a week when I set to work with the scientist. [ ]
A. would be
B. have been
C. had been
D. will be
承运人签发不清洁提单，表明（）。
A.提单本身不清洁
B.提单上载有货物外表状况不良的批注
C.提单上载有的货物表面不清洁
D.提单上被批注了“不清洁”字样
