【单选题】Which screw thread term is the nominal diameter？

A．He tortured his students when they screwed up in the class.

B．He encouraged his students when they made mistakes.

C．He was fired for his strict policies toward the students.

D．He was greatly honored by his students when he died.

A.If one engine fails，you do not lose control of the tow

B.It is more maneuverable

C.It develops more bollard pull for the same horsepower

D.It is generally subject to more propeller damage from debris in the water

A．support

B．sponsor

C．speed

D．screw

A．scraped

B．scribbled

C．screwed

D．sculpted

A.boss

B.knuckle

C.skeg

D.strut

A.You should stop to windward of the man and drift down on him

B.You should stop with the man on your weather beam and twist the ship up to him

C.A pickup off the weather bow gives maximum maneuverability with the least possibility of injury to the man

D.Ship pick up should never be used with a shallow draft vessel

A.Piston pump

B.Screw pump

C.Diffuser pump

D.Water-ring pump

A.Sheath-screw boom

B.Radial

C.Crescent

D.Quadrantal

A.Quadrantal

B.Gravity

C.Sheath-screw

D.Radial