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问题 选择题

本初子午线是

A．地球仪上的任意一条经线

B．是东、西经度的分界线

C．地球仪上的任意一条纬线

D．是东、西半球的分界线

答案

答案：B

本题主要考查的是地球的相关知识。所有的经线都称为子午线，但本初子午线是东、西经度的分界线。

单项选择题

The "Karat" marking on jewelry tells you what proportion of gold is mixed with other metals. If 14 parts of gold are mixed with 10 parts of base metal, the combination is called 14-Karat (14K) gold. The higher the Karat rating, the higher the proportion of gold in the object. The lowest Karat gold that can be marketed in the United States is 10-Karat gold. Jewelry does not have to be marked with its Karat quality, but most of it is. If there is a Karat quality mark, next to it must be the U.S. registered trademark of the person or company that will stand behind the mark, as required by the National Gold and Silver Stamping Act.

If a ring is stamped 24K, it has________.

A．204 parts of gold

B．24 parts of gold

C．two and four-tenths parts of gold

D．10 parts of gold
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单项选择题

国家对药品不良反应实行( )

A．随时报告制度
B．越级报告制度
C．定期报告制度
D．逐级报告制度
E．逐级、定期报告制度，必要时可以越级报告
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