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Will We Take Vacation"的相关试题:
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Will We Take Vacation in Spaces?
When Mike Kelly first set out to build his own private space-ferry service,he figured his bread-and-butter business would be lofting satellites into high-Earth orbit. Now he thinks he may have figured wrong.“People were always asking me when they could go,”says Kelly,who runs
Kelly Space TechnologT out of San Bernardino,Californi a.“I realized that real market is in space tourism.”
According to preliminary market surveys,there are 10,000 would-be-space-tourists willing to spend $1 million each to visit the final frontier. Space Adventure in Arlington,Virginia,has taken more than 1 30 deposits for a two-hour,$98,000 space tour tentatively(and somewhat dubiously)set to occur by 2005 .Gene Meyers of the Space Island Group says:“Space is the next exotic vacation spot.”
This may all sound great,but there are a few hurdles.Putting a simple satellite into orbit with no oxygen,life support or return trip necessary already costs an astronomical $22,000/kg.
And that doesn't include the cost of insuring rich and possibly litigious passenger. John Pike of the
Federation of American Scientists acerbically suggests that the entire group of entrepreneurs trying to corner the space tourism market have between them“just enough money to blow up one rocket.”The U .S.space agency has plenty of money but zero interest in making space less expensive for the little guys.So the little guys are racing to do what the government has failed to do:design a reusable launch system that's inexpensive,safe and reliable.Kelly Space's prototype looks like a plane that has sprouted rocket engines.Rotary Rocket in Redwood City,California,hasa booster with rotors make a helicopter-style return to Earth;Kistler Aerospace in Kirkland,Wash- ington,is piecing together its versions from old Soviet engines,shuttle-style thermal protection tiles and an elaborate parachute system.The first passenger countdowns are still years away,but bureaucrats at the Federal Aviation Administration in Washington are already informally discussing flight regulations.After all,you can't be too prepared for a trip to that galaxy far,far away.
For those who are intent on joining the 100-mile high club,Hilton and Budget are plotting to build space hotels.Before the Russian space Mir came down,some people were talking about using it as a low-rent space hotel to reduce the cost. If a space hotel is finally built in space,and if you're thinking of staying in it,you may want to check the Michelin ratings before booking yourself a suite.
Little guys,who do not have plenty of money but have great interest in space tourism,are trying to make the space travel less expensive but more reliable.
A.Right
B.Wrong
C.Not mentioned
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When We Are Asleep
Everyone dreams,but some people never recall their dreams,or do so very rarely.
Other people always wake up with vivid recollections（记忆）of their dreams, though they
forget them very quickly.In an average night of eight hours' sleep,an average adult will
dream for around one hundred minutes,probably having three to five dreams,each lasting
from ten to thirty minutes.
Scientists can detect when someone is having a dream by using an instrument which
measures the electrical waves in the brain.During dreaming,these waves move more
quickly.Breathing and pulse rate also increase,and there are rapid eye movements under
the lids，just as though the dreamer were really looking at moving objects.These signs of
dreaming have been detected in all mammals（哺乳动物）studied, including dogs,
monkeys, cats, and elephants, and also some birds and reptiles（爬行动物）.This period
of sleep is called the"D"state.Babies experience the"D"state for around 50%of their
sleep;the period reduces to around 25%by the age of 10.
Dreams take the form of stories,but they may be strange and with incidents not
connected,which make little sense.Dreams are seldom without people in them and they
are usually about people we know.One estimate says that two-thirds of the"cast"of our
dream dramas are friends and relations.Vision seems an essential part of dreams,except
for people blind from birth.Sound and touch are senses also often aroused,but smell and
taste are not frequently involved.In"normal"dreams,the dreamer may be taking part,or
be only an observer. But he or she cannot control what happens in the dream.
However,the dreamer does have control over one type of dream.This type of dream is
called a "lucid"（清醒的）dream. Not everyone is a lucid dreamer. Some people are
occasional lucid dreamers.Others can dream lucidly more or less all the time.In a lucid
dream,the dreamer knows that he is dreaming.
In a lucid dream we can use Morse code to communicate with others.
A.Right
B.Wrong
C.Not mentioned
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What We Take From and Give to the Sea
As long as we have been on earth,we have used the sea around us.We take from the ocean,and we give to it.
We take fishes from the ocean-millions of kilograms of fish,every year,to________(51)millions of people.We even_______(52)their bones for fertilizer.We take minerals from the ocean.One way to get salt is to_______(53)seawater in shallow basin and leave it until it evaporates（蒸发）.Along with salt,other minerals are left_______(54)evaporation.Much gold and silver drift dissolved in the waters of the sea,too.But the sea does not give them_______(55)by simple evaporation.________(56)gifts from the sea are pearls , sponges（海绵）and seaweed.Pearls________(57)jewelry.Natural sponges become cleaning aids.Seaweed becomes______(58)of many kinds一even candy,and ice cream一as well as medicine.Believe it or not,fresh water is another_______(59)from the sea.We cannot drink ocean water.Some of its contents may______(60)illness.But ocean water becomes fresh water when the salts are ________(61).In the future,we will find ourselves．________(62)more and more onfresh water from the sea.
The sea_______(63)us food,fertilizer,minerals,water,and other gifts.What do we give the sea?Garbage.We pollute the ocean_______(64)we use it as a garbage dump.Huge as it is,the ocean cannot hold all the water that we pour into it.________(65)garbage into the ocean is killing off sea life.Yet as the world population grows,we may need the sea and its gifts more than ever.
_________64
A.if
B.when
C.although
D.because
