移架，在顶板较好的情况下，移架工作在采煤机后滚筒之后1.5m处进_爱下问搜题

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问题判断题

移架，在顶板较好的情况下，移架工作在采煤机后滚筒之后1.5m处进行，一般不超过1—2m。

答案

参考答案：错

单项选择题

D

Any mistake made in the printing of a stamp raises its value. A mistake on one inexpensive postage stamp has made the stamp worth a million and a half times its original (本来的) value. The mistake was made more than a hundred years ago in the British colony (殖民地)of Mauritius, a small island in the Indian Ocean. In 1847 an order for stamps was sent to a London printer—Mauritius was to become the fourth country in the world to issue (发行) stamps.
Before the order was delivered(传达), a party was planned at Mauritius’Government House, and stamps were needed to send out the invitations. A local printer was told to copy the design for the stamps. He printed the words " Post Office " instead of " Post Paid " by mistake on the several hundred stamps that he printed.
Today there are only twenty-six of these misprinted stamps left—fourteen Onepenny Orangereds and twelve Twopenny Blues. Because of the Twopenny Blue’s rareness (稀少) and age, collectors have paid as much as $ 16800 for it.

In 1847 most countries of the world were ______.

A．not yet using stamps

B．collecting valuable stamps

C．buying stamps for Mauritius

D．printing their own stamps

单项选择题

喉痉挛时，首先应采取的措施是（）。

A.糖皮质激素

B.雾化吸入混悬麻黄碱

C.静注琥珀胆碱

D.托下颌，面罩吸氧，或持续正压辅助呼吸

E.放置口咽通气道