电阻钎焊包括()种加热方式。
A.2
B.3
C.4
参考答案:A
Owing to the slack demand ______ their products for the time being, they do not think it advisable to buy the machine.
A.of B.forC.on D.in
“或为辽东帽,清操厉冰雪。”“或为渡江楫,慷慨吞胡羯。”说的是哪两个人的典故?()
A.管宁、祖逖
B.祖逖、张巡
C.张巡、段秀实
D.段秀实、管宁