"The principal purpose of adjustment of the magnetic compass is to eliminate ______ as far as possible.
A.variation
B.compass error
C.deviation
D.Earth's magnetic force"
正确答案是C
"The principal purpose of adjustment of the magnetic compass is to eliminate ______ as far as possible.
A.variation
B.compass error
C.deviation
D.Earth's magnetic force"
正确答案是C