“三硬”厚煤层指的是：顶板硬、底板硬、煤质硬度f≈（）。
A.3
B.4
C.5
参考答案：B
Guang Zhou’s traffic facilities have been greatly improved _____ an advanced new light railway for the Asian Games.
A．as a result
B．thanks to
C．in case of
D．in response to
脑外面有3层被膜包裹，自外向内依次为
A．硬脑膜-蛛网膜-软脑膜B．软脑膜-蛛网膜-硬脑膜C．蛛网膜-软脑膜-硬脑膜D．硬脑膜-软脑膜-蛛网膜E．软脑膜-硬脑膜-蛛网膜
