31. Which type of bearing may be lubricated by seawater in a main propulsion shafting system?
(A) Thrust bearing
(B) Ball bearing
(C) Crosshead bearing
(D) Stern bearing
33. Which type of valve should be installed whenever an undesired reversal of flow is possible?
(A) Throttle valve
(B) Stop valve
(C) Check valve
(D) Relief valve
35. What is the most simple method of regulating steam flow in the steam supply to the turbine?
(A) Throttle valve control
(B) By-pass control
(C) Pressure regulating control
(D) Enthalpy control