以下对银汞合金的性质为不利因素的是（）
A.γ相
B.γ1相
C.γ2相
D.γ1相和γ2相
E.γ相和γ1相
参考答案：C
--- Driving on icy roads is very dangerous ! The more ice there is, the _______ down the road you have to look. You should be more careful.
--- OK, I will.
A．more far
B．farer
C．farther
D．farthest
锤击沉桩法的正常打桩方式采用()。
A、重锤高击，高锤重打
B、重锤低击，低锤重打
C、轻锤高击，高锤重打
D、重锤低击，低锤轻打
