中压碳素钢管、不锈耐酸钢管和低合金钢管,其焊接时坡口的加工方法为()。
A.气割
B.手提砂轮机加工
C.手工锉
D.车床加工
参考答案:D
工程物资
"Holmes!" I whispered. "What on earth are you doing in this disgusting place"
A. humble B. unpleasantC. underprivileged D. noisy