LOM距跑道入口9.0km，下滑角为3°，RDH=15m，则飞机正常过LOM的高为（）。

（ ） generally produces the most violent flying weather.

（ ） is the most easily recognized discontinuity across a front.

The transition zone where two different airmasses meet is called a （ ） ．

An altostratus cloud is classified in the （ ） cloud group.

Most clouds are composed of minute （ ） droplets.

When an airmass is warmed from below, its stability is （ ） ．

The tendency of an airmass to resist vertical motion is called （ ） ．

If an airmass forms over water, its classification is （ ） ．

（ ） results when the two airmasses are approximately equal in pressure.

（ ） is a weather phenomenon always associated with a thunderstorm.