转子流量计在有旁路的情况下如何投用？

申请国家助学贷款的借款人必须是具有完全行为能力的自然人，年龄需满（）周岁。

A.14

B.16

C.18

D.20

教育现代化的最高目标是人的现代化。( )

The recent dramatic increase in commuter airline crashes is caused in large part by pilot inexperience. As a major growth industry, the commuter airlines have recently had a great increase in the demand for experienced pilots. It is impossible to define and assess pilot experience, however. For example, someone with 1,000 hours of flight experience as an instructor in Arizona, where the weather is good, cannot be compared to someone with 1,000 hours’ experience as a night cargo pilot in the stormy northeastern United States.
The author’s conclusion that the dramatic increase in commuter airline crashes is caused by pilot inexperience is most weakened by the fact that the author has

A．argued that it is impossible to measure "pilot experience. "

B．used an example that does not relate logically to the point being illustrated.

C．provided only a partial explanation for the increase in commuter airline crashes.

D．made an unfair comparison between experience as a flight instructor and experience as a night cargo pilot.

E．(E) not specified how much of the recent increase in commuter airline crashes is due to pilot inexperience.

离子交换器再生时,再生液的（）。

A、浓度越大,再生度越大

B、浓度越小,再生度越大

C、浓度在一定范围(10%左右)内,再生度最大

D、对浓度没有严格的要求

对于形成杂质缺陷而言，高价正离子占据低价正离子位置时，该位置带有正电荷，为了保持电中性，会产生（）。

A.正离子空位

B.间隙负离子

C.负离子空位

D.A或B