印象中光总是来也匆匆，去也匆匆，让人抓不住踪迹，总希望能给光踩一脚刹车，看清它的模样，

________ causes strong winds and rough sea at northwest Bay of Biscay．

A.Strong low pressure

B.Strong high pressure

C.Steep pressure gradient

D.Steep gradient pressure

______causing strong winds and rough sea north west Bay of Biscay.

A.Strong low pressure

B.Strong high pressure

C.Steep pressure gradient

D.Steep gradient pressure

A ______ is created by a pressure gradient or slope in the water level．

A.gradient current

B.density current

C.swift current

D.torrent current

Pressure in a three dimerisional rectangular coordinate system is defined by the following equatiou:P=2xz+3y-5zy then the pressure gradient is______

Pressure in a three dimerisional rectangular coordinate system is defined by the following equatiou:P=2xz+3y-5zy then the pressure gradient is______

In reading a weather map, closely spaced pressure gradient lines would indicate ______.

A.high winds

B.high overcast clouds

C.calm or light winds

D.fog or steady rain

A pressure gauge is used to measure ().

A.pressure

B.temperature

C.force

What is a common unit of measure for atmospheric pressure ().

A.Centimeters

B.Inches

C.Degrees

D.Feet

A.a current will flow

B.a power will develop

C.a heat will flow

D.a pressure will produce

The most common instrument used to measure diesel engine exhaust pressure is the _____.

A.pyrometer

B.bourdon gauge

C.pneumercator

D.manometer