单项选择题
A.a margin of safety is provided should the line part B.the towline will wear more evenly C.there will be less stress on the towline D.a slight increase in speed will be realized
The forward movement of a ship in one revolution of its...
单项选择题The forward movement of a ship in one revolution of its propeller is measured by（）.
A.advance B.head reach C.pitch D.transfer
The distance that a ship moves forward with each revolu...
单项选择题The distance that a ship moves forward with each revolutionof its propeller，if there is no slip，is called（）.
The distance between rivets in a row is known as the（）....
单项选择题The distance between rivets in a row is known as the（）.
A.arm B.pitch C.gage D.rivet distance
