交通控制表示停止的灯是红灯，公共场所的安全门上是红灯，自行车、汽车的尾灯也是红灯。这些地方使用红灯的主要原因是( )。
A．红光鲜艳，易识别
B．红光波长长，穿透能力强，远处可以看到
C．红光波长短，穿透能力强，远处可以看到
D．从心理上分析，红光使人易警觉、兴奋
参考答案：B
解析： 在可见光中，红光是波长最长的光，空气对红光的散射作用最弱，也就是说红光的穿透力最强，可以传得最远，特别是下雨或大雾的日子里尤甚。故选B。
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| In the clinic, I asked if Michael could be retested, so the specialist tested him again.To my __1__, it was the same score. Later that evening, I __2__ told Frank what I had __3__ that day.After talking it over, we agreed that we knew our __4__ much better than an IQ test.We __5__ that Michael's score must have been a __6__ and we should treat him naturally as usual. We moved to Indiana in 1962, and Michael studied at Concordia High School in the same year.He got __7__ grades in the school, __8__ in biology and chemistry, which was a great comfort. Michael __9__ Indiana University in 1965 as a premedical student, soon afterwards, his teachers permitted him to take more courses than __10__.In 1968, he was accepted by the School of Medicine, Yale University. On graduation day in 1972, Frank and I __11__ the ceremony at Yale.After the ceremony, we told Michael about the low IQ score he got when he was six.Since that day, Michael sometimes would look at us and say __12__, "My dear mom and dad never told me that I couldn't be a doctor, not until after I graduated from medical school!" It is his special way of thanking us for the__13__ we had in him. Interestingly, Michael then asked for another IQ test.We went to the same clinic where he had __14__ the test eighteen years before.This time Michael scored 126, a(n) __15__ of 36 points.A result like that was supposed to be impossible. | ||||
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