单选题The piston moves up and down, thus causing the rotational movement of the（）AcrankshaftBconnecting rodCcross-headDmain beating
单选题
The piston moves up and down, thus causing the rotational movement of the（）
A
crankshaft
B
connecting rod
C
cross-head
D
main beating
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commonly, two approaches are frequently used to describe different processes of listening. they are ______. A、pre-listening model and post-listening modelB、bottom-up mo del and top-down modelC、pre-listening model and while-listening modelD、before- class model and after-class model
After issuing the show interfaces terse command, you notice that the status of one interface is "up down". What does this indicate?"() A.Layer 1 on the interface is up but Layer 2 is down.B.Layer 2 on the interface is up but Layer 3 has not been configured.C.The interface is administratively up but the link status is down.D.The interface is up but has been administratively turned off.
材料：A typical example of a hydraulic governor is the Woodward. This has adjustable droop for parallel operation and it is fitted with a speed-adjusting control . If required it can be fitted with a synchronizing motor to provide remote control from a switchboard.A gear pump driven from the engine supplies oil under pressure to accumulator pistons under which is a by-pass to regulate maximum pressure. One branch supplies oil which acts on top of the power piston, the pressure always tending to turn the terminal shaft to shut off fuel, while the other branch supplies oil to the pilot valve which is operated by the linkage from the fly weights above.Should the speed of the engine decrease due to increased load the flyweights will move towards their center of rotation and lower the position of the pilot valve plunger, admitting oil pressure from the bottom of the power piston. Since, however, the area on the bottom is much greater than the top the net resultant force causes the piston to move upwards. This operates the power lever turning the terminal shaft which varies the cut-off point in the fuel pump through linkage, but as the power piston moves up, the actuating compensating piston moves down.Oil under this piston is now forced through the needle valve to the receiving compensating piston, raising the outer end of the floating lever and the pilot valve plunger until it has returned to its normal position. This stops further movement of the terminal shaft so that the fuel control is now set in a position corresponding to the increased fuel required to run the engine at normal speed under the increased load.问题：This passage is mainly about ___.A.what type of governor should be provided when the engine is used for electric power generationB.why the speed of the engine fluctuatesC.how the governor worksD.how the fuel pumps workThe oil from the gear pump will ___. ① be supplied to the accumulator ② act on the power piston ③ be supplied to the pilot valveA.①B.①②C.②③D.①②③Which of the following is true about the Woodward discussed?A.It is a kind of mechanical governor.B.It can not be used for parallel operation.C.It has speed droop.D.It may only be manually controlled from a switch boarE.When the speed of the engine decreases due to increased load, which of the following will NOT happen?A.The flyweights move towards their centerB.The pilot valve plunger moves towards its normal positionC.The power piston moves downwards until it returns to its normal positionD.The terminal shaft moves to a new position请帮忙给出每个问题的正确答案和分析，谢谢！
键盘事件的执行顺序是（）。AKey Press、Key Down、Key UpBKey Down、Key Press、Key UpCKey Up、Key Down、Key PressDKey Up、Key Press、Key Down
The following output occurs on Router R1. IP SLA operation 1 uses an ICMP echo operation type, with default frequency of 60 seconds. The operation pings from address 1.1.1.1 to address 2.2.2.2. Which of the following answers is true reg arding IP SLA and object tracking on R1?（） R1# show track Track 2 IP SLA 1 state State is Up 3 changes, last change 00:00:03 Delay up 45 secs, down 55 secs Latest operation return code: OK Latest RTT (millisecs) 6 Tracked by: STATIC - IP - ROUTING 0A、The tracking return code fails after the SLA operation results in an ICMP echo failure three times.B、The tracking return code fails after the SLA operation results in an ICMP echo failure one time.C、After the tracking object fails, the tracking o bject moves back to an up state 45 seconds later in all cases.D、After moving to a down state, the tracking object moves back to an OK state 45 seconds after the SLA operation moves to an OK state.
下面当主接口由up转为down后哪种说法正确？（）A、当主接口由up转为down后，立即切换到备份接口。B、当主接口由down转为up后，立即切换回主接口。C、当主接口由up转为down后，等待一定时间后，若主接口状态仍为down，才切换到备份接口。D、当主接口由down转为up后，等待一定时间后，若主接口状态仍为up，才切换回主接口。
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单选题After issuing the show interfaces terse command, you notice that the status of one interface is "up down". What does this indicate?"（）ALayer 1 on the interface is up but Layer 2 is down.BLayer 2 on the interface is up but Layer 3 has not been configured.CThe interface is administratively up but the link status is down.DThe interface is up but has been administratively turned off.
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单选题In a diesel engine, when the fuel is injected into the cylinder,（）Athe piston is just coming upward from the bottom dead centerBthe piston has moved about one-fifth of the way upCthe piston has moved most of the way up and almost reached the TDCDthe piston has just past the TDC
单选题The （） is not properly set thus causing either advanced or retarded firing.ApistonBfuel injection pumpCcrankshaftDoil can
单选题The slippers run （） in the crosshead guides as the piston and rod are （）and prevent the top of the connecting rod from moving sideways.Aup and down；reciprocatingBup and down；rotatingCback and forth；reciprocatingDback and forth；rotating
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单选题In a large, low-speed diesel engine the clearance between the piston crown and cylinder head is found to be excessiveIn order to correct for this, you should（）Abuild up the piston crown by metal sprayingBbuild up the cylinder head by metal sprayingCinsert shims between the crankpin bearing box and the connecting rod footDinstall a thinner head gasket
单选题键盘事件的执行顺序是（）。AKey Press、Key Down、Key UpBKey Down、Key Press、Key UpCKey Up、Key Down、Key PressDKey Up、Key Press、Key Down
单选题While engine is in operation the piston moves up and down, thus causing the rotation of the （）.AcrankcaseBslipperCcam housingDcrankshaft
单选题The rotary motion of a diesel engine crankshaft is obtained from the up and down motion of the piston via the （）.AcamshaftBreduction gearsCrocker armDconnecting or piston rod
单选题The following output occurs on Router R1. IP SLA operation 1 uses an ICMP echo operation type, with default frequency of 60 seconds. The operation pings from address 1.1.1.1 to address 2.2.2.2. Which of the following answers is true reg arding IP SLA and object tracking on R1?（） R1# show track Track 2 IP SLA 1 state State is Up 3 changes, last change 00:00:03 Delay up 45 secs, down 55 secs Latest operation return code: OK Latest RTT (millisecs) 6 Tracked by: STATIC - IP - ROUTING 0AThe tracking return code fails after the SLA operation results in an ICMP echo failure three times.BThe tracking return code fails after the SLA operation results in an ICMP echo failure one time.CAfter the tracking object fails, the tracking o bject moves back to an up state 45 seconds later in all cases.DAfter moving to a down state, the tracking object moves back to an OK state 45 seconds after the SLA operation moves to an OK state.
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