The crank-room cover should not be opened until at least （） minutes after the engine stops.

[单选题]The diameter of the crank-pins should be measured with a （）.A . salinometerB . thermometerC . tachometerD . micrometer

[单选题]The crankcase cover should never be allowed to open for investigation when （）A . the engine stopsB . the engine is runningC . you repair the engineD . overhauling the engine

[单选题]The bridge should inform the engine room______before passing through congested or shallow waterway.A．24 hoursB．2 hoursC．1 hourD．15 minutes

[判断题]War risks should be added to the main insurance cover.（ ）A.对B.错

[判断题]War risks should be added to the main insurance cover.（ ）A.对B.错

[问答题]Study the following graphs carefully and write an essay in 160-200 words. Y

[单选题]Each crank is made up of two crank webs joined by a common（） to which the bottom endbearing is fitted.A . throwB . crankshaftC . crankpinD . crosshead

[单选题]With the crank in position in the engine, some measurements can be taken by a special bridge gauge and （）.A . a micrometerB . a bowlC . a feeler gaugeD . a wrench

[单选题]The crank chamber oil （）.A . can be recoveredB . is only supplied to cylindersC . only feeds the main bearingD . is a kind of detergent

[单选题]I've just locked my keys in my room. What should I do now_________A.Sorry,