用台虎钳夹紧工件时应注意哪些问题?
参考答案:
用台虎钳夹紧工件时,只允许依靠手臂的力量搬动手柄进行夹紧,绝不允许用锤子敲击手柄或用管子或其它工具随意接长手柄进行夹紧。
— I went to have the driving test this morning, but I didn’t pass it.
— ___________
A.Luck decides everything.
B.Better luck next time.
C.But you can drive well.
D.You are always unlucky.
对圆形截面轴心受压钢筋混凝土柱,以下哪些因素对提高柱子承载能力有效 Ⅰ.提高混凝土强度等级 Ⅱ.减小柱子的长细比 Ⅲ.箍筋形式改为螺旋式箍筋 Ⅳ.箍筋加密
A.Ⅰ、Ⅱ、Ⅲ、Ⅳ B.Ⅰ、Ⅱ、ⅢC.Ⅰ、Ⅲ、Ⅳ D.I、Ⅱ、Ⅳ