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根据以下材料，回答There is little debate about the firstdevelopment of the energy system of the 22nd century--that most of the energyproduced on a large scale will be in the form of electric power. Thus, most presentconcepts for major long-term energy sources (solar, geothermal, fusion) are basedupon electric power production at central plants.The second major development is thepotential use of hydrogen as both a basic fuel to replace natural gas and aspart of a general system to convert, store and transmit electric energy overlong district by fuel cells, or it could be used directly as a fuel forcommercial, industrial or transportation purposes.Although hydrogen seems likely to play amajor role in the future as a form of energy transport and storage, other processesmay also be useful. Here we note only two possibilities.Flywheels: It appears to be workable toconstruct flywheels of almost any needed size that would be efficientconverters (93-95 percent) in first storing and then releasing electric power.In addition, the kinetic (动力的) energy ofrotation is easily converted to alternating electric power. But the engineeringis at an early stage of development, and a decade or more may pass before this potentialcan be reliably estimated.Batteries and fuel cells: some of the manybatteries being developed today look quite promising. Within a decade or two, abattery-operated electric auto might even become competitive with today′ s vehicles,at least for driving ranges up to 200 miles. An electric automobile would bepollution-free,and would probably be more energy-efficient than theinternal-combustion (内燃) engine.A fuel cell (which may be considered a hydridebattery) with about 40 percent conversion efficiency is expected to enter powerproduction on a large scale within about five years. Unlike steam-poweredgenerators, fuel cells can be made large or small and their efficiency inoperation is essentially independent of the loading. Thus they may avoid mostof the distribution costs of electric power as well as provide pollution-fleepower and offer opportunities for using the "waste heat" effectively.The energy we use most todayis___________
A.solar energy B.geothermal energyC.hydrogen D.electricity

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根据以下材料，回答Hair loss can be destructive for themillions of men and women who experience it. Now scientists are reporting thata substance from honeybee hives might contain clues for developing a potentialnew therapy. They found that the material, called propolis, encouraged hairgrowth in mice. The study appears in A CS′ Journal of Agricultural and FoodChemistry. Ken Kobayashi and colleagues note that propolis is a resin-likematerial that honeybees use to seal small gaps in their hives. Not only does itwork as a physical barrier, but it also contains active compounds that fightfungal and bacterial invasions. People from ancient times had noticed propolis′special properties and used it to treat tumors, inflammation and wounds. Morerecently, research has shown that the substance promotes the growth of certaincells involved in hair growth though no one had yet tested whether that in turnwould result in new locks. Kobayashi ′ s team wanted to find out.When the researchers tested propolis onmice that had been shaved or waxed, the mice that received the treatment regrewtheir fur faster than those that didn′t. The scientists also noticed that afterthe topical application, the number of special cells involved in the process ofgrowing hair increased. Although they tried the material on mice that couldgrow fur rather than balding mice, the researchers note that hair lossconditions often result from abnormal inflammation. Propolis contains anti-inflammatorycompounds, so they expert it could help treat balding conditions.They add that further testing is needed tosee if the beehive material affects human hair follicles.What may cause hair loss according tothe passage?
A.Severe inflammation. B.Headache.C.Fungus. D.Cancer.

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根据以下材料，回答Trogmire Troll was dealing with acrisis. The new girl in class really liked him a lot. Trogmire was not happyabout it.Trogmire′s good friend, Tremor Troll, triedto comfort him. "What′s thebig deal? I think Treasure Troll is kind of cute. And she seems to be niceenough."Trogmire swallowed his last bite of poisonsumac salad and glared at Tremor. "Then why don′t you ask her to be yourgirlfriend? There she is, sitting all by herself at the other end of thecafeteria. March over there and ask her to be your sweetie-poo!""She′ s crazy about you, not me,"Tremor replied."Well, I don′t want any girlfriend,especially not a weird pesky one like her!" Trogmire growled.Tremor wouldn′ t give up. "The onlything pesky about her is that she keeps writing you those notes and shestares.""Yucky love notes!" Trogmireinterrupted. He took another sip of mole milk. "Did you notice those strange browneyes? Why aren′ t they normal red or pink?"Tremor took another look at Treasure."I think her face is a lovely shade of green. And her dark green curlyhair is quite pretty. Besides, she′ s very sweet and that′ s what reallymatters."Trogmire stuck out his tongue. "I think I′m going to be sick! I′dbetter save my dessert for later." He crammed a small bag of MaggotMunchies into his even smaller shirt pocket. "The fact is, I have aproblem. That girl is getting on my nerves!"Tremor followed Trogmire′s example anddecided to save his dessert for later. However, he carefully placed the baginto his lunch box. "Do youhave any ideas about how to solve your problem?" Tremor asked."I′m going to be mean and rude toher," Trogmire announced. "I′11 call her names and make ugly faces at her.""That′s how you treat everyone,"Tremor reminded his friend.Trogmire nodded. "It′s time thatTreasure got to know the real Troll!"How did Trogmire feel about Treasure?
A.He felt annoyed.B.He enjoyed the attention.C.He wasn' t aware that she existed.D.He was crazy about her.

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根据以下材料，回答Trogmire Troll was dealing with acrisis. The new girl in class really liked him a lot. Trogmire was not happyabout it.Trogmire′s good friend, Tremor Troll, triedto comfort him. "What′s thebig deal? I think Treasure Troll is kind of cute. And she seems to be niceenough."Trogmire swallowed his last bite of poisonsumac salad and glared at Tremor. "Then why don′t you ask her to be yourgirlfriend? There she is, sitting all by herself at the other end of thecafeteria. March over there and ask her to be your sweetie-poo!""She′ s crazy about you, not me,"Tremor replied."Well, I don′t want any girlfriend,especially not a weird pesky one like her!" Trogmire growled.Tremor wouldn′ t give up. "The onlything pesky about her is that she keeps writing you those notes and shestares.""Yucky love notes!" Trogmireinterrupted. He took another sip of mole milk. "Did you notice those strange browneyes? Why aren′ t they normal red or pink?"Tremor took another look at Treasure."I think her face is a lovely shade of green. And her dark green curlyhair is quite pretty. Besides, she′ s very sweet and that′ s what reallymatters."Trogmire stuck out his tongue. "I think I′m going to be sick! I′dbetter save my dessert for later." He crammed a small bag of MaggotMunchies into his even smaller shirt pocket. "The fact is, I have aproblem. That girl is getting on my nerves!"Tremor followed Trogmire′s example anddecided to save his dessert for later. However, he carefully placed the baginto his lunch box. "Do youhave any ideas about how to solve your problem?" Tremor asked."I′m going to be mean and rude toher," Trogmire announced. "I′11 call her names and make ugly faces at her.""That′s how you treat everyone,"Tremor reminded his friend.Trogmire nodded. "It′s time thatTreasure got to know the real Troll!"How did Treasure Troll feelabout Trogmire Troll?
A.She didn't like him because he was rude.B.She was annoyed by his strangeappearance.C.She didn' t have any strong feelingsabout him.D.She liked him a lot.

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根据以下材料，回答Hair loss can be destructive for themillions of men and women who experience it. Now scientists are reporting thata substance from honeybee hives might contain clues for developing a potentialnew therapy. They found that the material, called propolis, encouraged hairgrowth in mice. The study appears in A CS′ Journal of Agricultural and FoodChemistry. Ken Kobayashi and colleagues note that propolis is a resin-likematerial that honeybees use to seal small gaps in their hives. Not only does itwork as a physical barrier, but it also contains active compounds that fightfungal and bacterial invasions. People from ancient times had noticed propolis′special properties and used it to treat tumors, inflammation and wounds. Morerecently, research has shown that the substance promotes the growth of certaincells involved in hair growth though no one had yet tested whether that in turnwould result in new locks. Kobayashi ′ s team wanted to find out.When the researchers tested propolis onmice that had been shaved or waxed, the mice that received the treatment regrewtheir fur faster than those that didn′t. The scientists also noticed that afterthe topical application, the number of special cells involved in the process ofgrowing hair increased. Although they tried the material on mice that couldgrow fur rather than balding mice, the researchers note that hair lossconditions often result from abnormal inflammation. Propolis contains anti-inflammatorycompounds, so they expert it could help treat balding conditions.They add that further testing is needed tosee if the beehive material affects human hair follicles.The underline sentence in thefirst paragraph means ___________.
A.hair loss can't be repairedB.hair cut can be harmfulC.everyone must experience hair lossD.baldness can be ruinous for the victims

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根据以下材料，回答Trogmire Troll was dealing with acrisis. The new girl in class really liked him a lot. Trogmire was not happyabout it.Trogmire′s good friend, Tremor Troll, triedto comfort him. "What′s thebig deal? I think Treasure Troll is kind of cute. And she seems to be niceenough."Trogmire swallowed his last bite of poisonsumac salad and glared at Tremor. "Then why don′t you ask her to be yourgirlfriend? There she is, sitting all by herself at the other end of thecafeteria. March over there and ask her to be your sweetie-poo!""She′ s crazy about you, not me,"Tremor replied."Well, I don′t want any girlfriend,especially not a weird pesky one like her!" Trogmire growled.Tremor wouldn′ t give up. "The onlything pesky about her is that she keeps writing you those notes and shestares.""Yucky love notes!" Trogmireinterrupted. He took another sip of mole milk. "Did you notice those strange browneyes? Why aren′ t they normal red or pink?"Tremor took another look at Treasure."I think her face is a lovely shade of green. And her dark green curlyhair is quite pretty. Besides, she′ s very sweet and that′ s what reallymatters."Trogmire stuck out his tongue. "I think I′m going to be sick! I′dbetter save my dessert for later." He crammed a small bag of MaggotMunchies into his even smaller shirt pocket. "The fact is, I have aproblem. That girl is getting on my nerves!"Tremor followed Trogmire′s example anddecided to save his dessert for later. However, he carefully placed the baginto his lunch box. "Do youhave any ideas about how to solve your problem?" Tremor asked."I′m going to be mean and rude toher," Trogmire announced. "I′11 call her names and make ugly faces at her.""That′s how you treat everyone,"Tremor reminded his friend.Trogmire nodded. "It′s time thatTreasure got to know the real Troll!" Which of the following statements isTRUE?
A.Trogmire pretended to be rude in orderto make Treasure stop liking him.B.Tremor thought that looks were moreimportant than personality.C.Tremor thought that Treasure was cute.D.Trogmire offered his dessert to Treasureto make her sick.

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