气焊与气割的从业人员，操作前必须穿戴好符合国家有关标准规定的防护用品，严禁穿化纤工作服上岗。()
查看答案
The word "cheque-writers" (Para. 4) is closest in meaning to _____.
A. tycoons
B. donators
C. investors
D. celebrities
The phrase "a free lunch" (Para 1) implies that the free stuff on the Internet seems to be _____.
A. totally free
B. impossible as a free lunch
C. as right as the science
D. paid by someone you know
Which can be inferred from the first paragraph？
A. The quest for wisdom is an old-fashioned economic indicator.
B. When things proceed smoothly, people don"t need to go searching for wisdom.
C. Billionaires listed on the Forbes are demonstrating the profits of free market.
D. In the long run, all the wealthiest individuals will confess their ignorance.
焊嘴头被堵塞时，可将嘴头与平板摩擦，也可用通针清理，以消除堵塞物。()
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