The main function of piston compression rings is to （）

A . increase the density of the cylinder air charge B . prevent turbocharger overheating C . liminate the need for a pre-cooler D . remove moisture from air compressed by the turbocharger

A . stiffen the bedplate in way of the main bearings to increase the engines longitudinal strength B . accept most of the tensile loading that results from the firing forces developed during operation C . mount the engine frame securely to the hull to prevent shaft coupling misalignment D . connect the crosshead solidly to the piston rod

A . the information B . the formation C . the scatter D . the frictio

A . reduce fuel feeding B . increase fuel feeding C . keep original fuel feeding D . be overspeed

A . reduce the rolling of the vessel B . serve as the vessel's main strength member C . add strength to the bilge D . protect the vessel's hull when alongside a dock

A . refreshing the air B . making person upset C . adjusting the air humidity D . adjusting the air temperature

A . Evidence of the contract B . A receipt for the goods C . A document of title D . Evidence of the ship being seaworthine

A . Prevents lateral movement of the slow speed gear B . Transmits propeller thrust to the hull C . Keeps spring bearings in line D . Prevents main reduction gear axial movement

A . manages the CRS Server   B . creates CRS Engine reports   C . creates application scripts for call flows   D . remotely manages the LDAP Directory &e

A．To stop hackers from stealing your personal information. B．To disconnect your PC from the Internet when it is being attacked. C．To keep hidden software in your computers from leaking valuable information. D．To block hostile cookies and bugs from being planted on your computers.

A．Asking Swichen King's authorization for the purchase of a microwave oven. B．Reporting the survey result of buying a microwave oven to the general manager. C．Analyzing the necessity of buying a microwave oven for the staff. D．Introducing the suitable models of microwave oven to Swichen King.

A．A.headstock B．B.carriage C．C.tailstock D．D.chunk

A．For humor as well as reaffirming the difficulty with dressing for a big date. B．For indicating the author's embarrassment about how to dress. C．For opposing to so many dates among boys and girls. D．For disagreeing to the complexity of human dressing. 此题为多项选择题。

A. reduce friction B. carry away contaminants and debris C. prevent corrosion and seal for gases D. all of the above