阅读一篇短文，文中有15处空白，每个空白处给出了四个选项。应试者根据短文的内容从四个选项中选择一个最佳答案。
Space Research
Does walking on the moon make life better for people on earth? 51 all the problems of our own world，why should we be spending huge 52 on trips to outer space? Such questions as these are often asked，especially 53 those whose tax money is paying for space explorations．The answers to these questions are many and 54 ．
Up to now，the practical benefits resulting 55 space research have included the development of new methods and skills，new processes，new services，new products，and even new companies created to make use of what 56 through space travel．Also among the benefits 57 better education (especially in scientific subjects)， 58 management，higher quality of industrial products，and rapid 59 growth．People all over the world are now served by 60 weather predictions，better communication systems，and better understanding of the earth and its environment．Everyone will benefit 61 observations from space make 62 possible to measure the earth’s resources and 63 whether or not they are being used properly． 64 the space program will help our world deal with the problems of the environment．It has already brought a new appreciation of the complex system 65 man is only a part．
In addition to improving the quality of existing products，the space program has been responsible for the development and improvement of new ones．The most important is the computer．To bring the endangered Apollo 13 astronauts home safely in 1970，a new flight plan had to be made taking account of an unbelievably complex combination of elements．The computer accomplished this task in seventy-two minutes，whereas a man or a woman working with pencil and paper take more than a million years! If there had been no space program，it is doubtful that computers would now be so widely used in industry and government．
51．A．Consider B．Considering C．Considered D．Having considered
52．A．totals B．money C．sums D．dollars
53．A．to B．for C．by D．/
54．A．various B．variable C．varied D．variant
55．A．from B．in C．out of D．by
56．A．has learned B．has been learned C．is learned D．can 1eam
57．A．is B．are C．has D．was
58．A．effective B．efficient C．more effective D．effect
59．A．economic B．economical C．economics D．economy
60．A．improve B．improving C．improved D．being improved
6l．A．as B．unless C．although D．though
62．A．that B．it C．which D．/
63．A．observe B．observes C．observing D．to observe
64．A．Increasing B．Increased C．Increasingly D．To increase
65．A．which B．for which C．among which D．of which

答案
51．[B] 52．[C] 53．[C] 54．[A] 55．[A] 56．[B] 57．[B] 58．[C] 59．[A] 60．[C] 61．[A] 62．[B] 63．[D] 64．[C] 65．[D]