单项选择题
All of the following can be found on a Pilot Chart EXCEPT information concerning the（）.
A.percentage of frequency of wave heights B.percentage of poor visibility conditions C.sea surface temperatures D.amounts of precipitation
单项选择题 Air temperature varies with（）.
单项选择题 After a liferaft is launched，the operating cord（）.
单项选择题 Advection fog may be formed by cold air passing over a（）.
