单项选择题
A.cumulus
B.nimbus
C.stratus
D.cirrus
单项选择题 A local wind which occurs during the daytime and is caused by the different rates of warming of land and water is a().
单项选择题 A line on a weather chart connecting places which have the same barometric pressure is called an().
单项选择题 A feature of an inflatable raft which helps keep people stationary in rough weather is().