为了正确划分收入、费用的归属期，应遵守收付实现制原则。

什么叫导线的热膨胀？什么叫导线的热膨胀系数？

《卡萨布兰卡》是由电影大师希区柯克执导的吗？

Questions 14-23

·Look at the ten statements for this part.
·You will hear a passage about "A Research on Sleep ". You will listen to it twice.
·Decide whetheryou think each statement is right(R), wrong(W) or not mentioned(NM).
·Mark your answers on the Answer Sheet.

Extensive muscular inhibition happens during REM sleep.

A. Right

B. Wrong

C. Not Mentioned

屋面坡度大于（）%，不宜作为种植屋面。

A.25

B.50

C.75

D.100

流动的流体中的能量包括（）。

A、位能

B、压强能

C、动能

D、热能