The fog produced by warm moist air passing over a cold surface is called（）.

A.subtropical high pressure belt
B.intertropical convergence zone
C.doldrum belt
D.polar frontal zone

A.anticyclone
B.cold front
C.occluded front
D.cyclone

A.expose any loose connections
B.demagnetize the metal elements
C.bring the pointer to its true position
D.contract and expand the glass face