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焊接工程中的焊后液压强度试验常用水进行，试验压力为设计压力的()倍。
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某企业为扩大生产规模，修建一幢教学大楼，建筑面积为4300m2，类似工程的建筑面积为3200m2，预算成本为826900元，类似工程各种费用占预算成本的权重是：人工费8%、材料费65%、机械费12%、措施费9%、间接费15%、其他费8%；拟建工程地区与类似工程地区造价之间的差异系数为K1=1.03、K2=1.05、K3=0.90、K4=0.96、K5=1
That’s not good enough, however, the same stability that makes CFC so safe in industrial use makes them extremely longlives, some of the CFCs released today will still be in the atmosphere a century from now. Moreover, each atom of chlorine liberated form. a CFC can break up as many as 100,000 molecules of ozone.
For this reason, governments should ensure the careful handling and recycling of the CFC now in use. When plastic-foam burger holders are broken, the CFCs trapped inside escape. Discarded refrigerators re- lease CFCs as well, and, a significant part of the U.S. contribution to CFC emissions comes from draining automobile air conditioners. Such release of CFCs could be prevented if consumers and businesses were offered cash incentives to return brokendown air conditioners and refrigerators to auto and appliance dealers. Then the units could be sent back to the manufacturers so that the CFCs could be reused.
While recycling will help, the only sure way to save the ozone is a complete ban on CFC manufacture, which should be phased out over the next five years. Fortunately, as the Montreal Protocal demonstrates, banning CFCs will be far simpler than reducing other dangerous gases. But a ban could admittedly be economically disruptive to the entire world: the annual market for CFCs is some $ 2.2 billion. The Soviet Union, which is a heavy user of CFCs, will have a particularly tough time phasing out the chemicals. "I agree with the ban in principle, "said Vladimir Sakharov, a member of the Soviet State Committee for Enviromental Protection, "but in practice it will be extremely difficult. Our economy is not flexible as others."
To make the transition easier, chemical companies are working hard to find practical substitutes for CF- Cs. The most promising approach so far is to use CFC family members that are chemically altered to make them less dangerous to the environment. The chlorine - free substitutes is the high cost of making them. It may be that until better manufacturing techniques are developed, consumers will have to pay more for affected products. The prospect is not a pleasant one, it is a small price to pay for curbing tile green house effect and saving the life -preserving ozone layer.
Why should governments ensure tire careful handling and recycling of the CFCs now in use？
SECTION B INTERVIEW
Directions: In this section you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Questions 1 to 5 are based on an interview. At the end of the interview you will be given 10 seconds to answer each of the following five questions.
Now listen to the interview.
听力原文：Robinson: Li, I suggest we do a quick tour of central London. As it is Sunday, there is very little traffic. What do you think？
Li: That's a great idea, Robinson. What a wonderful view!
Robinson: It is, isn't it？ Now we are on the south bank of the Thames. You can see the Houses of Parliament and Big Ben from here. I used to work as a tourist guide when I was a student. Let's see if I can still do it. We're now crossing Lambeth Bridge into Westminster. Now we can turn right and drive past Westminster Abbey, where the kings and queens of England are crowned.
Li: What's that park on the left？
Robinson: That's St. James's Park. We'll drive back down here later. Now we're going along Whitehall. Number 10 Downing Street, where the Prime Minister lives, is on your left.
Li: Is that the one with the policeman standing outside？
Robinson: That's it. We're coming into Trafalgar Square. This is equally famous for its statue of Horatio Nelson and its pigeons.
Li: Horatio ... ？
Robinson: Nelson. The naval captain who defeated Napoleon at the battle of Trafalgar in 1805, and so stopped him from invading England. And this is Piccadilly Circus with its statue of the Greek god of love, Eros. This area we are coming into now is called Soho. This is London's Chinatown.
Li: Now I know where to come when I feel homesick!
Robinson: I hope you're not feeling homesick already. This area is the main entertainment district. You'll find most of the cinemas and theatres here. We're now going up Charing Cross Rd., and on your left is the world's biggest bookshop Foyles.
Li: Do they sell science books？
Robinson: They sell bodks on every subject and in most languages. Now we'll drive around the British Museum so that you can get your bearings.
Li: Isn't that where Marx used to collect the materials for Capital？
Robinson: That's right. He used to work in the British Museum Reading Room. You'll be working there too shortly. The University of London is only a few minutes walk from here. This is Oxford St., the main shopping district. Every British department store has a branch here.
Li: It's very quiet for a shopping centre.
Robinson: That's because it's Sunday. All the big shops are closed. The rest of the week it's crowded with tourists. Here we are at Marble Arch, at the northeast comer of Hyde Park.
Li: What are those people over there shouting about？
Robinson: That's Speaker's Comer. Every Sunday people come here to argue about every subject under the sun from how the earth is really flat to the danger of nuclear war.
Li: I must come here one Sunday.
Robinson: As a speaker or a heckler？
Li: Neither. As a spectator only!
Robinson: Now we're driving down Park Lane. On the left is Mayfair-the embassy quarter.
Li: Where is the Chinese Embassy？
Robinson: It's not here. It's in Portland Place, just south of Regent's Park.
Li: Is that Hyde Park on the right？
Robinson: It certainly is. And we're coming into Green Park now. We'll have a quick look at Buckingham Palace. Every morning at exactly 11:30, from April until the end of September, the Changing of the Guard takes place.
Li: So, that's the palace! By the way, is our College far from here？
Robinson: No, only about ten minutes. Now, we're coming into your neighbourhood.
From which place did they start their sightseeing？
A．When we are tired.B．When we cannot look at flowers.C．When we cannot change our lives
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