单项选择题
The net productivity per gang-hour can be improved through a decrease of（）.
A.cranes/derricks B.crane/derrick cycles C.crane/derrick cycle time D.weight per package
单项选择题 The patches where rust have been removed should be wiped clean before paint is（）.
单项选择题 The permant dunnage attached to the frames of the ship that aids in ventilation is (are) the（）.
单项选择题 The productivity of working shifts can be improved through a decrease of（）.
