题目内容
（请给出正确答案）
A.A disk or plate placed under a drinking glass to protect a table top.
B.A vessel engaged in coastal trade.
C.A roller coaster.
D.A resident of a coastal area.
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第1题
What is NOT true of the invisibility device? 查看材料
A.It is made of a special material with unusual ability.
B.Microwaves bounce off it when they strike it.
C.Microwaves pass through it when they strike it.
D.It bends the microwaves all the way around until they reach the opposite side.
第2题
What is true of microwaves? 查看材料
A.Their wavelengths are shorter than those of visible light.
B.Their wavelengths are longer than those of visible light.
C.They are different from visible light as they are a kind of radiant energy.
D.They are visible to the human eye.
第3题
根据以下材料，回答题
Invisibility Ring
Scientists can"t yet make an invisibility cloak like the one that Harry Potter uses. But， for the first time， they"ve constructed a simple cloaking device that makes itself and something placed inside it invisible to microwaves.
When a person "sees" an object， his or her eye senses many different waves of visible light as they bounce off the object. The eye and brain then work together to organize the sensations and reconstruct the object"s original shape. So， to make an object invisible， scientists have to keep waves from bouncing off it. And they have to make sure the object casts no shadow. Otherwise， the absence of reflected light on one side would give the object away.
Invisibility isn"t possible yet with waves of light that the human eye can see. But it is now possible with microwaves. Like visible light， microwaves are a form. of radiant energy. They are part of the electromagnetic spectrum， which also includes radio waves， infrared light， ultravioletmys， X rays， and gamma rays. The wave lengths of microwaves are shorter than those of radio waves but longer than those of visible light.
The scientists" new "invisibility device" is the size of a drink coaster and shaped likearing. The ring is made of a special material with unusual ability. When microwaves strike thering， very few bounce off it. Instead， they pass through the ring， which bends the waves all the way around until they reach the opposite side. The waves then return to their original paths.
To a detector set up to receive microwaves on the other side of the ring， it looks as if the waves never changed their paths as if there were no object in the way! So， the ring is effectively invisible.
When the researchers put a small copper loop inside the ring， it， too， is nearly invisible.
However， the cloaking device and anything inside it do cast a pale shadow. And the device works only for microwaves， not for visible light or any kind of electromagnetic radiation. So， Harry Potter"s invisibility cloak doesn"t have any real competition yet.
Harry Potter is mentioned in the passage， because scientists __________. 查看材料
A.can now make an invisible cloak of the same kind as he uses
B.try to make an invisible cloak of the same kind as he uses
C.try to invent a device similar in idea to the invisible cloak he uses
D.know that it is possible to make an invisible cloak of the same kind
第4题
The author thinks that 查看材料
A.packing is actually useless and could be ignored
B.people will soon stop using packaging altogether
C.enough research has been done into recycling
D.it is better to produce new materials than to re—tlSe old ones
第5题
Some environmentalists think that __________. 查看材料
A.plastic packaging should be made more convenient
B.no alternative can be found to plastic packaging
C.too much plastic is wasted
D.shops should stop using plastic containers
第6题
材料
A.experimenting with the use of paper bottles
B.giving up the use of glass bottles
C.increasing the use of plastic bottles
D.re-using their paper containers
第7题
根据以下材料，回答题
The Issue of Package
Maybe everyone has such an experience that you have to unwrap several layers of packaging when you enjoy a piece of candy. But this overuse of wrapping is not confined to luxuries. It is becoming increasingly difficult to buy anything that is not done up in beautiful wrapping.
The package itself is of no interest to the shopper， who usually throws it away immediately. So why is it done? Some of it， like the cellophane on meat， is necessary， but most of the rest is simply competitive selling. This is absurd. Packaging is using up scarce energy and resources and messing up the environment.
Recycling is already happening with milk bottles which are returned to the dairies， washed out，and refilled. But both glass and paper are being threatened by the growing use of plastic. More dairies are experimenting with plastic bottles.
The trouble with plastic is that it does not rot. Some environmentalists argue that the only solution to the problem of ever increasing plastic containers is to do away with plastic altogether in the shops， a suggestion unacceptable to many manufacturers who say there is no alternative to their handy plastic packs.
It is evident that more research is needed into the recovery and reuse of various materials and into the cost of collecting and recycling containers as opposed to producing new ones. Unnecessary packaging， intended to be used just once， and make things look better so more people will buy them， is clearly becoming increasingly absurd. But it is not so much a question of doing away with packaging as using it sensibly. What is needed now is a more advanced approach to using scarce resources for what is， after all， a relatively unimportant function.
"This overuse of wrapping is not confined to luxuries. " （Line 2， Paragraph 1） means __________. 查看材料
A.more wrapping is needed for ordinary products
B.more wrapping is used for luxuries than for ordinary products
C.too much wrapping is used for both luxury and ordinary products
D.the wrapping used for luxury products is unnecessary
第8题
查看材料
A.in your body
B.without water
C.before long
D.for a change
E.on a busy day
F.to your weight
第9题
查看材料
A.in your body
B.without water
C.before long
D.for a change
E.on a busy day
F.to your weight
第10题
根据以下材料，回答题
The Drink Your Body Needs Most
（1） Our bodies are estimated to be about 60% to 70% water. Blood is mostly water， and our muscles， lungs， and brain all contain a lot of water. Water is needed to regulate body temperature and to provide the means for nutrients （滋养物） to travel to all our organs. Water also transports oxygen to our cells， removes waste， and protects our joints and organs.
（2） We lose water through urination （排尿）， respiration （ 呼吸 ）， and by sweating. If you are very active， you lose more water than if you do not take much exercise. Symptoms of mild dehydration （脱水） include chronic pains in joints and muscles， lower back pain， headaches，and constipation （便秘）. A strong smell to your urine， along with a yellow color indicates that you are not getting enough water. Thirst is all obvious sign of dehydration and in fact， you need water long before you feel thirsty.
（3） A good rule of thumb （好的做法） is to take your body weight in pounds and divide that number in half. That gives you the number of ounces （盎司） of water per day that you need.
For example， if you weigh 160 pounds， you should drink at least 80 ounces of water per day.
If you exercise you should drink another 8ounce glass of water for every 20 minutes you are active. If you drink coffee or alcohol， you should add at least an equal amount of water. When you are traveling on an airplane， it is good to have 8 ounces of water for every hour you are on board the plane.
（4） It may be difficult to drink enough water on a busy day. Be sure you have water handy at all times by keeping a bottle for water with you when you are working， traveling， or exercising. If you get bored with plain water， add a bit of lemon for a touch of flavor. There are some brands of flavored water available， but some of them have sugar or artificial sweeteners that you don"t need.
Paragraph 1 __________ 查看材料
A.Ounces of water needed per day
B.Importance of water
C.Composition of water
D.Signs of dehydration
E.Supply of water
F.Necessity for bringing a bottle for water
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