单项选择题
A.Thin，metal，air tight cell
B.Curved tube containing alcohol
C.Column of mercury supported by atmospheric pressure
D.Expansion of mercury in a closed tube
单项选择题 MODERATE WAVES，TAKING A MORE PRONOUNCED LONG FORM；MANY WHITE HORSES ARE FORMED.THIS sea condition is likely to be termed（）.
单项选择题 In the Northern Hemisphere，winds veering sharply to the west or northwest with increasing speed are indications that a（）.
单项选择题 In the Northern Hemisphere，what type of cloud formations would you expect to see to the west of an approaching tropical wave?（）.