二氧化碳气体保护焊的气瓶满瓶时压力为()。
A、2.5MPA
B、7.0MPA
C、8.5MPA
D、9.5MPA
参考答案:B
—Hello, is that Jack speaking?
—Hold on, please. He’s coming right now.
A.I’m sorry
B.Wait a moment
C.Don’t wait
D.Take a message