不容错过，青海师范大学自考学前教育（专科）专业介绍

债券流通市场是( )

A．债券转让交易活动的总称

B．债券一级市场

C．股票市场的一个重要补充

D．以上都不对

Have you heard about new compact Discs? They're the latest invention from Sony. A CD consists of a piece of aluminium coated with transparent plastic，12 cms across，for producing sound.

It's similar to an ordinary record，except that it's read by a laser beam，and the information recorded on the aluminium is digital.

The makers claim that a CD can reproduce the original sound perfectly，without any distortion or background hiss. As the system is computerized，there's no loss of quality between the studio master and the record you buy.

Also，a CD is much tougher-than a vinyl(乙烯基)record，so it doesn't need such careful handling. Dust and dirt won't damage it，and as there's no contact between the laser and the disc, it will never wear out.

Passage Two

Questions 26 to 30 are based on the following passage.

We all know that humans are damaging the environment, but what can we do about it? Some people are trying to do their bit to be more environmentally friendly.

Local councils in Britain encourage certain aspects of green living, such as recycling paper, tin, plastic and glass. They want to reduce the amount of rubbish going into landfill sites（填埋场），because they are running out of places to dump（倾倒）rubbish. In some areas rubbish for recycling is collected from your doorstep, but in other areas, you have to take it to a special recycling place, such as a bottle bank.

Another way of reducing the amount of rubbish you create is to use reusable products instead of disposable ones For example, some people use strong shopping bags or boxes for their groceries instead of plastic carrier bags, or use washable nappies instead of disposables.

More people are becoming interested in reducing their carbon footprint—the amount of carbon they use up. They try to reduce their carbon emissions（释放）by cycling, using public transport or an electric car, rather than driving gas-consuming vehicles. Some people choose not to fly for holiday trips because planes are the biggest producers of carbon emissions.

You can make‘green’ choices when buying food too. It's best to buy food which was locally grown or produced so that it hasn't been imported by air, or shipped by road from far away.

Houses can be environmentally friendly too. It takes less energy to heat a house if it has good insulation（绝缘，隔热）and double glazing (双层玻璃）．You can also create your own energy it you have solar panels or a wind turbine fitted though these can be expensive. You can also save water by using a rain water container for washing the car or watering the garden. It's even possible to use a system where‘grey water’—water which has been through a tap（水龙头）once already, is used to flush（冲洗）toilets. Some new housing projects are being built specifically to be as environmentally friendly as possible.

26．The purpose of collecting reusable wastes is to＿．

A．save energy consumed in daily life

B．reduce the amount of rubbish dumped

C．create a new way of green living

D．decrease the amount of carbon produced

设方阵A满足A3-2A+E=0，则（A2-2E）-1=_________.