试题与答案

属于材料物理性能的是()A、强度 B、硬度 C、热膨胀性 D、耐腐蚀性

题型:单项选择题

题目:

属于材料物理性能的是()

A、强度

B、硬度

C、热膨胀性

D、耐腐蚀性

答案:

参考答案:C

试题推荐
题型:阅读理解

阅读理解。

     About 130 years ago, Thomas Edison of the US invented the light bulb (电灯). Edison's bulb has turned

night into day ever since. But today, many want to turn the light off.

     The European Union (欧盟) recently decided that by 2009, people should stop using the Edison-style light

bulb. Instead, they should use compact fluorescent lamps (小型荧光灯, CFLs节能灯).

    "CFLs save energy and last longer. They can save money in the long run," said a British official. CFLs use

67 percent (67%) less electricity than the older bulbs. They last up to 10 times (倍) longer. Scientists say that

if everyone used CFLs, electricity use would be cut by 18 percent. There would also be much smaller amounts

of greenhouse gases (温室气体) given off.

     But it's difficult to make people change their lighting habits. First the CFLs are more expensive. They cost

eight times the price of the older bulbs. Many people don't like the CFL bulb. They find it too bright. You

cannot change the light of a CFL, either.

     CFLs have been around for several years. However, the older lights still make up about two-thirds (2/3) of

total (全部的) light bulb sales.

( )1. Thomas, Edison invented the CFL bulb 130 years ago.

( )2. Countries in the European Union will not use Edison-style bulbs by 2009.

( )3. Using CFLs helps protect the environment.

( )4. If you get an older bulb for l Euro (欧元), the CFL bulb will cost you 8 Euros.

( )5. CFLs have been widely used instead of the older bulbs for several years.

查看答案
微信公众账号搜索答案