人的全面发展的历史条件。

阅读理解。

     Zipped into a bag, it looks like a large umbrella. Unfolded, it goes along the street like any other bicycle.

     It's the "A-bike", the brainchild (脑力劳动的产物) of British inventor Sir Cive Sinclair, who made history

in the 1970s hy devel oping the world's first pocket calculator. He described his new invention as "the world's

smallest, lightest foldable bicycle".

     "My original thought was that if you could have a bicycle that was dramatically lighter and more firm than

the ones that exist today, it would change the way in which bicycles are used," said Sinclair.

     The mini-bike showed in Singapore last week and set to go on sale worldwide in 2005 at a price of nearly

US $300, is built for riders as heavy as 112 kilograms and is height-adjustable (可调整高度的). It takes about

20 seconds to fold or unfold.

     Its wheels are a quarter the size of those on a regular bicycle, but Sinclair promises a smooth ride for most

cyclists. "You require no extra energy to ride the A-bike and it can go up to 15 miles per hour (24 kilometers

per hour)," he said. Constructed mainly of plastic, the 5.5-kilogram bicycle folds into a package of less than

0.03 cubic meters (立方米).

     Sinclair also invented the first pocket TV in 1984 and the futuristic C5 electric tricycle in 1985. He said he

hoped the bicycle would attract common citizens, officials, campers or anyone needing transport for a short

trip and he said the next step for the A-bike was to add an electric motor in a few years.

1. The most important character of this kind of bike is its _____.

A. hig size

B. light weight

C. beautiful appearance

D. foldable structure

2. The wheels of a regular bicycle is _____ the size of this kind of bike.

A. four times

B. three times

C. one-fourth

D. one-third

3. This kind of new bike is mainly made of _____.

A. plastic

B. packages

C. bags

D. metal

4. The best title of the text is _____.

A. World's smallest foldable bicycle arriving

B. A new bike a large umbrella

C. A foldable bike, a large bag

D. A great inventor of a new bike

5. This kind of new bike hasn't been fixed with _____.

A. a wheel

B. an electric motor

C. pedal

D. a hand

Bedazzling (眼花缭乱) with their bright colors and eye-catching displays, fireworks light up our night skies during the holidays. However, these crowd-pleasers can have some damaging side effects.

Once a firework is set off, it only takes a couple of seconds before smoke, dust and harmful chemicals are let out into the atmosphere. The loud booming noises are caused by gunpowder. While the sounds may excite some people, they can be frightening to domestic and wild animals — as well as some humans.

The pretty colors you see are a result of more chemicals. Barium, added to make green, is known for its poisonous and radioactive qualities. Blue comes from copper compounds. Cadmium, lithium and lead — all found in fireworks — have been linked to diseases, such as allergies and skin rashes in both humans and animals. Acid rain has been linked to gases given off by fireworks, which sometimes go beyond the toxin(毒素) limits of the United States Clean Air Act.

Once all those chemicals come back down to the ground, they can cause problems too. Debris (碎片) from the fireworks falls to the ground, where animals can burn their paws or noses on piping hot pieces. Humans also are at risk of stepping on or picking up something sharp or hot. Meanwhile, debris that finds its way into waterways can damage animal habitats and water supply sources.                              

Instead of setting off fireworks, try to come up with some new ways for fun. Here are some ideas to get you started:

• Sky lanterns — a tradition that originated long ago in the most-populated Asian country.

•  Party crackers — a favorite in the United Kingdom — give you noise and surprises without the mess of fireworks. You can make your own or buy eco-friendly crackers.

• Want noise excitement with less volume? Consider a fireworks sound recording beforehand or break out the party horns (号角) and blow up a storm! 

46. The advantages of fireworks can be seen below EXCEPT that _____.

A. the special sounds of fireworks excite people

B. debris from fireworks can even find its way into water

C. the pretty and bright colors add to the beauty of night skies

D. fireworks are enjoyed as one of the crowd-pleasers

47. Which of the following is NOT true according to the passage?

A. Copper compounds are needed to make green in fireworks.

B. Chemicals in fireworks are both poisonous and dangerous.

C. Too much gases from fireworks can result in acid rain.

D. Chemicals in fireworks are harmful in the air and on the ground.

48. All the underlined words are probably _____________.

A. mineral materials                             B. tiny solids

C. chemical elements                                   D. broken pieces

49. What is implied from the passage?

A. Gunpowder in fireworks makes loud booming noises.

B. It must be Indians who first started to hang sky lanterns.

C. Fireworks does less harm in the air than on the ground.

D. Fireworks can even break the balance of nature.

50. What can be concluded as the writer’s attitude towards fireworks?

A. It is not allowed to set off fireworks except during the holidays.

B. Fireworks should be banned and replaced by some other means.

C. Night is the best time to set off fireworks and see the pretty colors.

D. You cannot set off fireworks unless you come up with new ways.

延期申报的纳税人必须（）。

A.经过税务机关的批准

B.在核准期限内按税务机关核定的税额预交税款

C.在核准期限内按上期实际缴纳税额预交税款

D.在核准期限内按实缴纳税款

用同样大小的电流通入长度相同而直径分别为25mm、50mm的园棒时，直径25mm的表面磁感应强度近似为直径50mm的2倍