某井采用 * * 衡钻井方式,对于气井,附加泥浆密度正确的是().
A、0.07g/Cm3
B、0.12g/Cm3
C、0.20g/Cm3
D、0.03g/Cm3
参考答案:B
Mary is really good at taking notes in class. She can _______ almost every word her teacher says.
A.put out
B.put down
C.put away
D.put together
所谓左焊法是指焊丝和焊炬从左端向右端移动的操作方法。( )