单选题   Questions18-20 are based on the recording you have just heard.
单选题    
 
【正确答案】 B
【答案解析】[听力原文] Good evening. In 1959, on the day that I was born, a headline in Life magazine proclaimed 'Target Venus: There May be Life There!' It told of how scientists rode a balloon to an altitude of 80,000 feet to make telescope observations of Venus's atmosphere, and how their discover~/of water raised hopes that there could be living things there. As a kid I thrilled to tales of adventure in Isaac Asimov's juvenile science-fiction novel Lucky Starr and the Oceans of Venus. For many of my peers, though, Venus quickly lost its romance. The very first thing that scientists discovered with a mission to another planet was that Venus was not at all the earthly paradise that fiction had portrayed. It is nearly identical to our own planet in bulk properties such as mass, density, and size. But its surface has been cooked and dried by an ocean of carbon dioxide. Trapped in the burning death-grip of a runaway greenhouse effect, Venus has long been held up as a cautionary tale for everything that could go wrong on a planet like Earth. As a possible home for alien life, it has been voted the planet least likely to succeed. But I have refused to give up on Venus, and over the years my stubborn loyalty has been justified. The rocky views glimpsed by Venera 9 and other Russian landers suggested a tortured volcanic history. That was confirmed in the early 1990s by the American Magellan orbiter, which used radar to peer through the planet's thick clouds and map out a rich, varied, and dynamic surface. The surface formed mostly in the last billion years, which makes it fresher and more recently active than any rocky planet other than Earth. Russian and American spacecraft also found hints that its ancient climate might have been wetter, cooler, and possibly even friendly to life. Measurements of density and composition imply that Venus originally formed out of basically the same stuff as Earth. That presumably included much more water than the tiny trace we find blowing in the thick air today. Thus our picture of Venus at around the time life was getting started on Earth is one of warm oceans, probably rich with organic molecules, splashing around rocky shores and volcanic vents. The sun was considerably less bright back then. So, Venus was arguably a cozier habitat for life than Earth. What do we learn from the Life magazine article? 事实细节题。讲话者提到,《生活》杂志上的一篇文章讲述了科学家们乘坐气球到8万英尺的高空,在那里用望远镜观察金星的大气层,他们发现了金星上有水的存在,这燃起了他们对金星上有生命存在的希望。
单选题    
 
【正确答案】 A
【答案解析】[听力原文] What are scientists' findings about Venus? 事实细节题讲话者提到,金星在质量、密度和大小等体积特性方面与地球几乎相同。
单选题    
 
【正确答案】 B
【答案解析】[听力原文] What information did Russian and American space probes provide about Venus? 事实细节题。讲座中提到,俄罗斯和美国的太空探测器发现了金星古时候的气候可能比现在更加湿润、清凉,比现在更加适合生物生存的线索。