单选题Critical speeds occurring within the operating speed range of a main propulsion diesel engine may be changed, or have their damaging effects reduced by a/an （）Aengine support vibration isolatorBdetuner or viscous fluid damperClightened crankshaft flywheelDspherically seated crankshaft bearing
单选题
Critical speeds occurring within the operating speed range of a main propulsion diesel engine may be changed, or have their damaging effects reduced by a/an （）
A
engine support vibration isolator
B
detuner or viscous fluid damper
C
lightened crankshaft flywheel
D
spherically seated crankshaft bearing
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