单项选择题
The preferred method of controlling external bleeding is by（）.
A.direct pressure on the wound B.elevating the wounded area C.pressure on a pressure point D.a tourniquet above the wound
单项选择题 The pitch of a propeller is a measure of the（）.
单项选择题 The main reason a long towline is used during an oceantow is that（）.
单项选择题 The forward movement of a ship in one revolution of its propeller is measured by（）.
