单项选择题
A.areas where special materials are used B.hazardous areas C.location of emergency repair equipment D.type and strength of materials used
A Kort nozzle is a(n)（）.A.hollow tube surrounding the p...
单项选择题A Kort nozzle is a(n)（）.
A.hollow tube surrounding the propeller used to improve thrust B.nozzle attached to a firefighting hose C.intake valve on a diesel engine D.piston cylinder on a diesel engine
A hydraulic accumulator aboard a ship is designed to（）....
单项选择题A hydraulic accumulator aboard a ship is designed to（）.
A.store fluid under pressure B.act as a fluid reservoir C.provide overpressure relief D.replenish fluid to a system
A fuel-air mixture below the lower explosive limit is t...
单项选择题A fuel-air mixture below the lower explosive limit is too（）.
A.rich to burn B.lean to burn C.cool to burn D.dense to burn
