One advantage of the all-purpose nozzle is that it（）.

A . It increases its volume B . It reduces its volume C . It has less product per volume D . None of the above

A . high temperature distillate can be re- circulated to induce additional flashing B . scale formation is not a severe problem C . cold shocking is more effective in removing scale D . water purity is greatly increased at high capacity

A . will not jam on the mooring line B . is stronger C . is easier to use when under heavy tension D . is safer to use when under heavy tensio

A . that the transmitter is on the bridge B . that local manual control can be achieved C . that remote control can be achieved D . simple in construction and reliable in operatio

A . less jerky starts B . less jerky stops C . overheating worries D . none of the overheating worrie

A . Inefficient scavenging；twice B . Inefficient scavenging；1~8 times C . Fewer strokes in a circle；twice D . Fewer strokes in a circle；1~8 time

A . it is fitted with neoprene O-ring seals B . the honing process makes it easier to maintain the desired oil film C . there is likelihood of water leaking into the combustion space D . it fits more loosely due to a decrease in heat transfer through the composite wall

A . lower thermal expansion rates than wet liners B . greater heat transfer rate than wet liners C . greater wear resistance than wet liners D . procedure to replace dry liners is simpler than for wet liner

A . the range of antenna can cover everywhere in the world B . we can know the ship’s exact position C . that the distress alert can be located as soon as possible D . antenna of permanent earth stations may be directed towards fixed points in the sky

A．are reorganized more often B．give more lectures to students C．qualify more technical graduates D．revolutionize many walks of life

A.lower thermal expansion rates than wet liners B.greater heat transfer rate than wet liners C.greater wear resistance than wet liners D.procedure to replace dry liners is simpler than for wet liners

Recounting that anecdote to journalists in New York this week, Mr. Annan sought to explain why a draft declaration on UN reform. and tackling world poverty, due to be endorsed by some 150 heads of state and government at a world summit in the city on September 14th16th, had turned into such a pale shadow of the proposals that he himself had put forward in March. "With 191 member states", he sighed, "it's not easy to get an agreement." Most countries put the blame on the United States, in the form. of its abrasive new ambassador, John Bolton, for insisting at the end of August on hundreds of last minute amendments and a line-by-line renegotiation of a text most others had thought was almost settled. But a group of middle-income developing nations, including Pakistan, Cuba, Iran, Egypt, Syria and Venezuela, also came up with plenty of last-minute changes of their own. The risk of having no document at all, and thus nothing for the world's leaders to come to New York for, was averted only by marathon all-night and all-weekend talks. The 35-page final document is not wholly devoid of substance. It calls for the creation of a Peacebuilding Commission to supervise the reconstruction of countries after wars; the replacement of the discredited UN Commission on Human Rights by a supposedly tougher Human Rights Council; the recognition of a new "responsibility to protect" peoples from genocide and other atrocities when national authorities fail to take action, including, if necessary, by force; and an "early" reform. of the Security Council. Although much pared down, all these proposals have at least survived. Others have not. Either they proved so contentious that they were omitted altogether, such as the sections on disarmament and non-proliferation and the International Criminal Court, or they were watered down to little more than empty platitudes. The important section on collective security and the use of force no longer even mentions the vexed issue of pre-emptive strikes; meanwhile the section on terrorism condemns it "in all its forms and manifestations, committed by whomever, wherever and for whatever purposes", but fails to provide the clear definition the Americans wanted. Both Mr. Annan and, more surprisingly, George Bush have nevertheless sought to put a good face on things, with Mr. Annan describing the summit document as "an important step forward" and Mr. Bush saying the UN had taken "the first steps" towards reform. Mr. Annan and Mr. Bolton are determined to go a lot further. It is now up to the General Assembly to flesh out the document's skeleton proposals and propose new ones. But its chances of success appear slim. Who have recently listened to the story in the first paragraph of the text？ A．Ambassadors. B．UN officials. C．The world's leaders. D．Reporters.

When our population is so small that all our labor can be engaged in the group represented by A, productivity of labor (and therefore wages) will be at their maximum. When our population increases so that some of the labor will have to be set to work in group B, the wages of all labor must decline to the level of the productivity in that group. But no employer, without government aid, will yet be able to afford to hire labor to exploit the opportunities represented by C and D, unless there is a further increase in population. But suppose that the political party in power holds the belief that we should produce every thing that we consume, that the opportunities represented by C and D should be exploited. The commodities that the industries composing C and D will produce have been hitherto obtained from abroad in exchange for commodities produced by A and B. The government now renders this difficulty by placing high duties upon the former class of commodities. This meads that workers in A and B must pay higher prices for what they buy, but do not receive higher prices for what they sell. After the duty has gone into effect and the prices of commodities that can be produced by C and D have risen sufficiently, enterprisers will be able to hire labor at the wages prevailing in A and B, and establish industries in C and D. So far as the remaining laborers in A and B buy the products of C and D, the difference between the price which they pay for those products and the price that they would pay if they were permitted to import those products duty-free is a tax paid not to the government, but to the producers in C and D, to enable the latter to remain in business. It is an uncompensated deduction from the natural earnings of the laborers in A and B. Nor are the workers in C and D paid as much, estimated in purchasing power, as they would have received if they had been allowed to remain in A and B under the earlier conditions. When C and D are established, workers in these industries______. A．receive higher wages than do the workers in A and B B．receive lower wages than do the workers in A and B C．are not affected so adversely by the levying of duties as are workers in A and B D．receive wages equal to those workers in A and B

A、They trade throughout the day. B、They offer greater diversification. C、They have smaller bid-ask spreads.

A．It is easier to terminate and install than copper cabling． B．It is able to carry signals much farther than copper cabling． C．It is usually cheaper than copper cabling． D．It is able to be installed around sharp bends．