We now know that about all the kinds of seaweed are animals.A. one fourthB. one fourth o

We now know that about ____ of all the kinds of seaweed are animals.

A: one four

B: once four

C: once fourth

D: one fourth

A.assess

B.limit

C.arrange

D.apply

A、What

B、Why

C、How

D、That

A.It’s not possible to predict the futur

B.Black holes have changed the laws of physics.

C.Time travel may one day be possibl

D.We now know Einstein was right about everythin

E.

A．We should clean the banks of our rivers

B．We should know what will happen in the future

C．We should know what we should do and do it now

D．We should plant more trees and flowers

A．"Are there any answers that you would like to change,now that you have had time to think things over"

B．"Others in your organization have provided conflicting information． Do we have your permission to explain your point of view"

C．"Do you mind if we check your answers out with others in future interviews"

D．"Is there anything we haven’t touched on that you think is important for me to know"

Dear Sir or Madam

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ing to kill us. Twenty-five years ago, tiffs was the only question about AIDS we couJd anwer with any certainty; now, it is the only question we really camaot answer well at all. By now, those of us in the AIDS business long term have cared for thousands of patients. No one with that kind of personal experience can doubt for a moment the deadly potential of H. I. V. or the life-saving capabilities of the drugs developed against it. But there are also now htmdreds of footnotes and exceptions and modifications to those two facts that make the big picture ever murkier (扑朔迷离). We have patients scattered at every possible point: men and women who cruise on their medications with no problems at all, and those who never become stable on them and die of AIDS; those who refuse them until it is too late, and those who never need them at all; those who leave AIDS far behind only to die from lung cancer or breast cancer or liver failure, and those few who are killed by the medications themelves. So, when we welcome a new patient into our world, one whose fated place in this world is still unclear, and that patient asks us, as most do, whether this illness is going to kill him or not, it often takes a bit of mental stammering (口吃 ) before we hazard an answer,Now, a complete rundown of all the news from the front would take hours. The statistics change almost; hourly as new treatments appear. It is all too cold, too mathematical, too scary to dump on the head of a sick, frightened person. So we simplify. "We have good treatments now, we say. "You should do fine. " Once, not so long ago, we were working in another universe.Now we have simply rejoined the carnival (嘉年华) of modern medicine, noisy and encouraging, confusing and contradictory, fueled by the eternal balancing of benefits and risks. You can.win big, and why shouldnt you, with the usual fall-safe combination of luck and money. You have our very best hopes, so step right up: we sell big miracles but, offer no guarantees. What does the author say about AIDS？

A.It is definitely deadly twenty-five years ago.

B.The patients want to know everything about it.

C.We can answer anything about it with certainty now.

D.We could not answer questions about it well before.

outgrowing the planet Earth and the time had come to take the information superhighway to outer space.

“The Internet is growing quickly, and we still have a lot of work to do to cover the planet.” Cerf told the first day of the annual conference of Internet Society in Geneva where more than 1500 cyberspace fans have gathered to seek answers to questions about the tangled web of the Internet.

Cerf believed that it would soon be possible to send real-time science data on the Internet from a space mission orbiting another planet such as Mars. “There is now an effort under way to design and build an interplanetary Internet. The space research community is coming closer and closer and merging. We think that we will see interplanetary Internet networks that look very much like the ones we use today. We will need interplanetary gateways and there will be protocols to transmit data between these gateways, ” Cerf said.

Francois Fluckiger, a scientist attending the conference from the European Particle Physics Laboratory near Geneva, was not entirely convinced, saying: “We need dreams like this. But I don’t know any Martian whom I’d like to communicate with through the Internet.”

Cerf has been working with NASA’s Pasadena Jet Propulsion Laboratory—the people behind the recent Mars expedition—to design what he calls an “interplanetary Internet protocol.” He believes that astronauts will want to use the Internet, although special problems remain with interference and delay.

“This is quite real. The effort is becoming extraordinarily concrete over the next few months because the next Mars mission is in planning stages now,” Cerf told the conference.

“If we use domain names like Earth or Mars...jet propulsion laboratory people would be coming together with people from the Internet community.” He added.

“The idea is to take the interplanetary Internet design and make it a part of the infrastructure of the Mars mission.”

He later told a news conference that designing this system now would prepare mankind for future technological advances.

“The whole idea is to create an architecture so the design works anywhere. I don’t know where we’re going to have to put it but my guess is that we’ll be going out there some time,” Cerf said.

“If you think 100 years from now, it is entirely possible that what will be purely research 50 years from now will become commercial 100 years from now. The Internet was the same—it started as pure research but now it is commercialized.”

第31题：According to Cerf, the purpose to design interplanetary internet is to _____.

［A］ send real-time science data

［B］ communicate with astronauts

［C］ lay foundation for future technological advances

［D］ commercialize the technology