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根据下列文章,请回答 36~40 题。Eta Carinae As possibly the galaxy’s(银河)most massive star,Eta Carinae is now engaging in some very unusual behaviour,Australian astronomers,being in the Southern Hemisphere(半球),are able to observe it clearly. In the l9th century,Eta Carinae was for a time the third brightest star in the sky.it has now become less bright so that binoculars(双筒望远镜)are needed to see it.“It seems to be brightening and becoming less bright over a period of many years”,said Dr Bob Duncan from the Australia Telescope National Facility. While it is not unusual for stars to vary in brightness,the period is usually much shorter.“Since l992 it has become four times brighter,and then last year it began to drop dramatically,”he said. The problem in observing Eta Carinae is that it has been surrounded by a cloud of gas and dust, it hard to see tile star directly.However,radio waves and infrared light(红外线)can pass through this cloud,SO telescopes that receive these wavelengths can observe what is occurring. Eta Carinae is of particular interest to astronomers because it seems to be in its death throes(剧痛).Being so large it will end up as a supernova(超).There has not been a supernova in our galaxy since the invention of tile telescope. While a l987 explosion in a nearby galaxy gave astronomers plenty of valuable data,they are hungry for an even closer look. Eta Carinae has other unique features.and is the only star known to produce an ultraviolet(紫外线)laser that is brighter than that produced by the Sun.Lasers have been observed in other frequencies from a few stars. 第36题:Eta Carinae is now engaging in

A.
some very common behaviour.
B.
some very dull behaviour.
C.
some very frightening behaviour.
D.
some very strange behaviour.
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刷刷题刷刷变学霸
举一反三

【单选题】下列哪项是中波紫外线的作用

A.
杀菌
B.
增强免疫
C.
消肿
D.
降血压
E.
缩血管

【单选题】下列属于红外线应用的是

A.
杀菌
B.
监测森林火情
C.
使日光灯管发光
D.
促进人体维生素D合成