活塞发生器校准精密声级计，声级计频率计权特性应选择（）。A、L

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问题单项选择题

活塞发生器校准精密声级计，声级计频率计权特性应选择（）。

A、L

B、A

C、B

D、C

E、滤波器

答案

参考答案：A

选择题

— Could you introduce to me a high quality English dictionary for high school students?

— Sure. _______ well for several years, this kind of dictionary is very popular.

A．Selling

B．To sell

C．Sold

D．Being sold

选择题

—What's the date today?

—_________. [ ]

A. It's sunny

B. It's June 14th

C. It's 9 o'clock

D. It's Saturday