你可能感興趣的試題

The recording fathometer produces a graphic record of the（）.

A.bottom contour only up to depths of 100 fathoms
B.depth underneath the keel against a time base
C.contour of the bottom against a distance base
D.depth of water against a distance base

單項(xiàng)選擇題

The points on the earth’s surface where the magnetic dip is 90° are（）.

A.Along the magnetic equator
B.Connected by the isoclinal line
C.The isopors
D.The magnetic poles