题干

.如图,半圆形玻璃砖置于光屏PQ的左下方。一束白光沿半径方向从A点射入玻璃砖,在O点发生反射和折射,折射光在光屏上呈现七色光带。若入射点由A向B缓慢移动,并保持白光沿半径方向入射到O点,观察到各色光在光屏上陆续消失。在光带未完全消失之前,反射光的强度变化以及光屏上最先消失的光分别是

A:减弱,紫光

B:减弱,红光

C:增强,紫光

D:增强,红光

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C

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    The increasing environmental problems and need for eco-friendly products and services are creating a new job section of green-collar jobs.____It is expected that by 2025 about 25% of the jobs in developed countries will be of green-collar jobs. Doesn't the data look promising for the future?

    ____And jobs will pop up at every income level, from environmental manager to gardener. For example, many countries including the United States have understood that fossil fuels have negative effect on the environment which can later become a serious danger to mankind.____The increasing demand of newer resources has created the need for experts and researchers who can find better ways to deal with the ongoing needs. In addition, in order to meet the increasing demand of environment-friendly equipment, both green product designer and trained workers are needed. Management of environmental organizations also demands a large number of environmental managers.

    ____ Internet is undoubtedly the best way to find information on almost any matter. Nowadays, different kinds of jobs are being posted online. Search through a couple of job websites to look for a bright future in energy conversion and recycling of waste management. Check regularly and find the right work for yourself.____

A. People who read newspapers can also find different kinds of green-collar jobs.

B. People who take green careers will be well paid.

C. Where can you find green-collar jobs?

D. Green-collar jobs have become a bright career chance for all.

E. Many countries have realized the importance and need for energy-saving products and services.

F. Therefore, possibilities are being explored to find alternatives to meet demands in a better way.

G. Forget the blue–collar and white–collar categories.