制造钳工用手用锯条应当选用（）。
A.T12钢经淬火和低温回火
B.Cr12Mo钢经淬火和低温回火
C.65钢淬火后中温回火
参考答案：A
_______ of hope still remains for the young girl whose cruel step father poured a pan of boiling water
over her head as she _______ to remove the basin on the stove which was too hot for a bruised bare
hand. [ ]
A. A light; denied
B. A ray; turned down
C. A little; rejected
D. A ray; refused
随着人们生活水平的提高，汽车逐渐走进了寻常百姓家。如图3，设某小轿车现连人带车总重为1.5×103千克，当汽车通过一圆弧半径为50米的拱桥顶点时，速度为10m／s，此时汽车对桥面的压力为 ( )
A．0
B．3000N
C．1.2×104N
D．1.5×104N
