单项选择题
The （） is used for hauling in or letting out the wires or ropes.
A.windlass B.anchor capstan C.turning gear D.winch barrel
单项选择题 （） may be fitted for operating the derrick topping lift (the wire which adjusts the derrick height).
单项选择题 （） provides the head or pressure to supply the domestic water where required.
单项选择题 Under rotary pumps are the gear, （）, cam-and-piston and screw types.
