（）is the volume for loading goods of the vehicle.

A:Vehicle tonnage B:Vehicle size C:Vehicle capacity D:Available Vehicle capacity

（）is the volume for loading goods of the vehicle.

A:Vehicle tonnage B:Vehicle size C:Vehicle capacity D:Available vehicle capacity

As in the field of space travel, so in undersea exploration new technologies continue to appear. They share a number of similarities with each other — as well as some important differences.
Manned submersibles (潜水器), like spaceships, must maintain living conditions in an unnatural environment. But while a spaceship must simply be sealed against the vacuum of space, a submersible must be able to bear extreme pressure if it is not to break up in deep water.
In exploring space, unmanned vehicles were employed before astronauts. In undersea exploration, on the other hand, men paved the way, only recently have unmanned remote-operated vehicles (ROVs) been put to use.
One reason for this is that communicating with vehicles in orbit is much easier than talking to these underwater. A vacuum am ideal medium for radio communications, but underwater communications are limited to much slower sound waves. Thus, most undersea vehicles—particularly ROVs— operate at the end of long ropes.
For a similar reason, knowing where you are undersea is much more difficult than in space. A spaceship’s position can be located by following its radio signal, or by using telescopes and radar. For an undersea vehicle, however, a special network of sonar (声纳) must be laid out in advance on the ocean’ floor in the area of a dive to locate the vehicle’s position.
Though undersea exploration is more challenging than outer space in a number of respects, it has a distinct advantage: Going to the ocean depths doesn’t require the power necessary to escape Earth’s gravity. Thus, it remains far less expensive.

The sonar devices must be placed （　）.

A:from time to time B:after the undersea vehicle dives C:at the time when the undersea vehicle is diving D:before the undersea vehicle dives

{{B}}第二篇{{/B}}

The sonar devices must be placed ______.

A:from time to time B:after the undersea vehicle dives C:at the time when the undersea vehicle is diving D:before the undersea vehicle dives

? ?阅读下面的短文，文中有15处空白，每处空白给出4个选项。请根据短文的内容，从4个选项中选择1个最佳答案。

? ?A new computer system has been designed to stop ships sinking. The greatest danger to a holed vessel is that flooding of its compartments will make the {{U}}?(51) ?{{/U}} unstable enough to capsize. It is estimated that nearly half the ship {{U}}?(52) ?{{/U}} during the Second World War capsized because of loss of {{U}}?(53) ?{{/U}}.
? ?Pacer System of Burlington, Massachusetts has now refined a system devised by a reserve U.S. Navy officer, Stephen Drabouski. The computer is programmed with every possible eventuality of flood damage. Once the actual damage is keyed into the computer the operator is told by the computer {{U}}?(54) ?{{/U}} the implications are—and what can be done to re-establish the vessel.
? ?Trials on the American aircraft carrier USS Midway have {{U}}?(55) ?{{/U}} that the re action time to damage can be cut to a fiftieth. An incident was simulated in which the ship was {{U}}?(56) ?{{/U}} by two Exocet missiles causing flooding to 30 {{U}}?(57) ?{{/U}} receipt of the flood damage information in the damage control centre to a full printout of damage, effects, {{U}}?(58) ?{{/U}} countermeasures and an assessment of the result of the countermeasures.
? ?In a re-run of the incident {{U}}?(59) ?{{/U}} the computer program the damage control officer took four and a quarter hours to establish the effects, of the damage and another four hours {{U}}?(60) ?{{/U}} a decision could be taken on countermeasures.
? ?Although the system can be used to provide {{U}}?(61) ?{{/U}} control officers with advice, they do not, of course, have to {{U}}?(62) ?{{/U}} the information. Quite often the " {{U}}?(63) ?{{/U}} solution" will be unacceptable for operational reasons. When that happens the system can be asked for alternatives or the operator {{U}}?(64) ?{{/U}} interrogate the computer to find out what would happen if the officer’s {{U}}?(65) ?{{/U}} solution was put into action.

A:remote B:safety C:damage D:vessel

“船舶；车辆”正确的翻译为( )。

A:vessel; vehicle B:ship; cargo C:vehicle; vessel D:cargo; vehicle

汉译英：“船舶；车辆”，正确的翻译为( )。

A:vessel；vehicle B:ship；cargo C:vchicle；vessel D:cargo；vehicle

若已定义了类Vehicle，则下列派生类定义中，错误的是

A:class Car：Vehicle｛／＊类体略*／｝， B:class Car：public Car｛／＊类体略＊／｝； C:class Car：public Vehicle｛／＊类体略＊／｝； D:class Car：virtual public Vehicle｛／＊类体略＊／｝；

若已定义了类Vehicle，则下列派生类定义中，错误的是（）。

A:class Car：Vehicle{/*类体略*/}， B:class Car：public Car{/*类体略*/}； C:class Car：public Vehicle{/*类体略*/}； D:class Car：virtual public Vehicle{/*类体略*/}；