（）焊接工艺存在高频电磁场辐射有害因素
A.电焊
B.氩弧焊
C.熔化焊
参考答案：B
(2013·重庆，35)—Forgotten something？I can keep an eye on your kids if you want to go and get it.
—________.Thank you all the same.
A．It's very kind of you.
B．Oh，how careless of me!
C．I might as well go and get it.
D．Well，I can do without it.
平地机液压系统为闭式系统。（）
