The function of direct current regulated power supply is to input an alternating current power of 220volts, so that it can output __________.

A . Transportation B . Distribution C . Sending goods D . carrying goods

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 . increases with latitude，being maximum at the geographic poles B . decreases with latitude，being maximum at the geographic equator C . is greatest when a vessel is near the Earth's magnetic equator D . remains the same at all latitude

A . equatorial current B . humidity C . rotation of the earth D . change of seaso

A . at B . for C . in D . o

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 . directly from high pressure toward low pressure B . directly from low pressure toward high pressure C . from high pressure toward low pressure deflected by the earth's rotation D . from low pressure toward high pressure deflected by the earth's rotatio

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 . cloud movement B . vessel heading C . waves D . swell

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.

The "last barrier"(Para. 3) mentioned in Melano's e-mail refers to A．the old culture of curiosity. B．lack of direct communication. C．racial and cultural relations. D．the differences between people.

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

Telecities will supersede megacities for several reasons, including the drive toward clean air, reducing pollution, energy conservation, more jobs based on services, and coping with the high cost of urban property. Now we must add the need to cope with terrorist threats in a high-technology world. Western mind-sets were clearly jolted in the wake of the terrorist attack on the World Trade Center in New York City and attacks in Indonesia, Saudi Arabia, and else where. But the risks posed by twentieth-century patterns of urbanization and architecture have ye to register fully with political figures and leaders of industry. The Pentagon, for example, has been rebuilt in situation rather than distributed to multiple locations and connected by secure landlines and broadband wireless systems. Likewise, the reconstruction of the World Trade Center complex still represents a massive concentration of humanity and infrastructure. This is a remarkably shortsighted and dangerous vision of the future. The security risks, economic expenses, and environmental hazards of over-centralization are everywhere, and they do not stop with skyscrapers and large governmental structures. There are risks also at seaports and airports, in food and water supplies, at nuclear power plants and hydroelectric turbines at major dams, in transportation systems, and in information and communications systems. This vulnerability applies not only to terrorist threats but also to human error, such as system-wide blackouts in North America in August 2003 and in Italy in September 2003, and natural disasters such as typhoons, hurricanes, floods, and earthquakes. Leaders and planners are only slowly becoming aware that overcentralized facilities are the most vulnerable to attack or catastrophic destruction. There is also growing awareness that new broadband electronic systems now allow governments and corporations to safeguard their key assets and people in new and innovative ways. So far, corporations have been quickest to adjust to these new realities, and some governments have begun to adjust as well. Which of the following statements is true according to the passage？ A．The telecity is a TV manufacturing city. B．The telecity is a city of the speed and bandwidth of networks. C．Singapore is closer to New York than Arkadelphia, Arkansas is in telecity age. D．Singapore is actually closer to New York than Arkadelphia, Arkansas.

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