Tides are superimposed on nontidal rising and falling water levels，caused by（）．

A . marline B . sail twine C . tape D . wire

A . five ten-dollar bills B . five ten-dollars bill C . five ten dollars bill

A . administrators B . system monitoring C . network operator D . power users E . admin F . users’ assistant

A . mean low water B . the same as that used for the charts of the locality C . the highest possible level D . given in table three of the tide table

A . mean low water B . mean lower low water C . mean high water D . mean high water spring

A . auxiliary guys B . extra fair leads C . steel bands D . sto

A . Sheath-screw davits B . Gravity davits C . Radial davits D . Quadrantal davit

A . an above-deck datum such as the top of the ullage pipe B . the tank ceiling aboard transversely framed vessels C . the tank top D . a thievage mark below the edge of the deck

A . open B . open front type C . live front type D . None of the above

A .  line timing B .  loop timing C .  internal timing D .  through timing E .  external timing

A . to make VTP easier to implement B . to isolate broadcast traffic C . to increase the size of the collision domain D . to allow more devices to connect to the network E . to logically group hosts according to function F . to increase network security

A . The boat should be hoisted a few inches clear of the cradle before cranking out the davits B . The inboard gripes should be cast off before the outboard gripes C . The outboard section of the cradle must be released D . The tricing pendants will automatically bring the boat alongside at the embarkation deck

A . not B . no C . any D . none

A . Diurna B . Semi-diurnal C . Solar D . Mixed

A . line timing B . loop timing C . internal timing D . through timing E . external timing

A . self-propelled，inspected vessels B . towing vessels C . recreational vessels D . uninspected passenger vessel

A . fuel tanks B . spark plugs C . carburetors D . distributor

A . assist in drydock alignment B . improve the vessel's stability C . protect the vessel from slamming against piers D . reduce the rolling of the vessel

A. to make VTP easier to implement B. to isolate broadcast traffic C. to increase the size of the collision domain D. to allow more devices to connect to the network E. to logically group hosts according to function F. to increase network security

A．/ B．A C．An D．The