Ring check主要用于检测和消除用户侧的环网，Ring check报文格式描述正确的是哪些？（）A、DMAC为ONT系统MACB、SMAC为桥MACC、DMAC为广播MAC值为0xFFD、SMAC为ONT系统MAC
Ring check主要用于检测和消除用户侧的环网，Ring check报文格式描述正确的是哪些？（）
- A、DMAC为ONT系统MAC
- B、SMAC为桥MAC
- C、DMAC为广播MAC值为0xFF
- D、SMAC为ONT系统MAC
相关考题：
In a diesel engine, when refitting piston rings you should ①check the ring gap at the smallest diameter of the cylinder ②remove carbon from the ring grooveA.①B.②C.①②D.neither ① nor ②
In a diesel engine, when refitting piston rings you should______. I. check the ring gap at the smallest diameter of the cylinder II. remove carbon from the ring grooveA.I onlyB.II onlyC.both I and IID.neither I nor II
备锚，摇“备车”钟。（）A、Get anchor ready and ring “Stand by engine”.B、Get anchor ready and ring “Finished with engine”.C、Get mooring ready and ring “Stand by engine”.D、Get mooring ready and ring “Finished with engine”.
一般局域网采用（）和环型令牌网Token Ring为主。A、广域网WAN（Wide Area Network）B、城域网MAN（Metropolitan Area Network）C、共享介质局域网（Shared LAN）D、总线以太网Ethernet
单选题In large, low-speed, main propulsion diesel engine, position ring groove wear usually occurs at the（）Atop of the ring grooveBback of the ring grooveCbottom of the ring grooveDpiston ring end clearance
单选题备锚，摇“备车”钟。（）AGet anchor ready and ring “Stand by engine”.BGet anchor ready and ring “Finished with engine”.CGet mooring ready and ring “Stand by engine”.DGet mooring ready and ring “Finished with engine”.
单选题A diesel engine piston ring face is in direct contact with the （）.Atop of the ring grooveBcylinder liner oil filmCbottom of the ring grooveDback of the ring groove
单选题In a diesel engine, when refitting piston rings you should （） Ⅰ.check the ring gap at the smallest diameter of the cylinder Ⅱ. Remove carbon from the ring grooveAⅠ onlyBⅡ onlyCboth Ⅰ and ⅡDneither Ⅰ nor Ⅱ
单选题A condition contributing to diesel engine piston rings sticking in the ring grooves, is insufficient ring clearance at the ring（） Ⅰ.gap Ⅱ.sideAⅠonlyBⅡ onlyCboth Ⅰ and ⅡDneither Ⅰ nor Ⅱ
单选题Diesel engine piston ring blow-by is usually caused by excessive ring clearance at the ring（）AbackBsideCgapDbottom
单选题In the sentence “In some designs the cylinder oil is timed so that the oil injects only on the piston ring belt, the "piston ring belt" means （）.Apiston crownBpiston ring grooveCpiston skirtDpiston ring area
单选题A condition contributing to diesel engine piston rings sticking in the ring grooves, is insufficient ring clearance at the ring（）AgapBsideCbackDradial
多选题Ring check主要用于检测和消除用户侧的环网，Ring check报文格式描述正确的是哪些？（）ADMAC为ONT系统MACBSMAC为桥MACCDMAC为广播MAC值为0xFFDSMAC为ONT系统MAC
单选题On a ship，how many ring buoys are required to have a buoyant line attached?（）AOne ring life buoyBOne ring life buoy on each side of the shipCThree ring life buoysDTwo ring life buoys on each side of the ship
单选题If the compression rings on a diesel engine piston become stuck in the ring groove, the cause may be due to（）Aexcessive ring actionBexcessive ring temperatureCimproper ring rotationDexcessive ring face wear
单选题In a diesel engine, when installing new piston rings it is important to check（） Ⅰ.ring gap clearance Ⅱ.side clearanceAⅠ onlyBⅡ onlyCboth Ⅰ and ⅡDneither Ⅰnor Ⅱ
单选题When installing rings on a diesel engine piston, you should check the ring（）Adiametrical tensionBgap clearanceCradial thicknessDface thickness