题干

日常生活中,当打开或关闭电灯时,会从附近的收音机中听到“喀喀”的杂音,这杂音的产生原因是(  )

A:电路通断时发出的电磁波被收音机接收

B:电路通断时收音机内元件因放电冒出火花

C:通断电路的瞬间电流过大将机内元件烧坏

D:收音机内有灰尘等杂物

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答案(点此获取答案解析)

A

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阅读理解

    Green is an important color in nature. It is the color of grass and the leaves on trees. It is also the color of most growing plants.

    Sometimes, the word green means young, fresh and growing. Sometimes, it describes something that is not yet ripe or finished. For example, a greenhorn is someone who has no experience, who is new to a situation. In the fifteenth century, a greenhorn was a young cow or ox whose horns(角) had not yet developed. A century later, a greenhorn was a soldier who had not yet had any experience in battle. By the eighteenth century, a greenhorn had the meaning it has today—a person who is new in a job.

    Someone who has the ability to grow plants well is said to have a green thumb. The expression comes from early nineteen hundreds. A person with a green thumb seems to have a magic touch that makes plants grow quickly and well. You might say that the woman next door has a green thumb if her garden continues to grow long after your plants have died.

    The Green Revolution is the name given some years ago to the development of new kinds of rice and other grains. The new plants produced much larger crops. The Green Revolution was the result of hard work by agricultural scientists who had green thumbs.

    Green is also the color used to describe the powerful feeling, jealousy(嫉妒). The green-eyed monster is not a frightening creature from outer space. It is an expression used about four hundred years ago by British writer William Shakespeare in his play “Othello”. It describes the unpleasant feeling a person has when someone has something he wants. A young man may suffer from the green-eyed monster if his girlfriend begins going out with someone else. Or, that green-eyed monster may affect your friend if you get a pay rise and he does not.