[简答题]Had electronic computers not been invented，__________(很多关于太空飞行的问题不能解决了)．

[简答题]Had electronic computers not been invented，__________(很多关于太空飞行的问题不能解决了)．

[单项选择]Electronic computers （　）, the complicated mathematical operations, such as weather forecast and the control of satellites, can be done quickly and accurately.
A. being used
B. used
C. having been used
D. to be used

[简答题]Electronic computers, which have many advantages, cannot carry out creative work and replace man.

[简答题]Electronic computers, which make it possible to free man from the labor of complex measurements and computations, have found wide applications in engineering.

[单项选择]Without electronic computers, much of today’s advanced technology （　） achieved．
A. will not have been
B. have not been
C. would not have been
D. had not been

[单项选择]The______of electronic computers has opened up new ways of data analysis for the scientist.
A. advent
B. adverse
C. advert
D. advise

[单项选择]The ______ of electronic computers has opened up new ways of data analysis for the scientist.
A. advent
B. adverse
C. advert
D. advise

[单项选择]Much unfriendly feeling towards computers has been based on the fear of widespread unemployment resulting from their introduction.Computers are often used as part of automated (自动化的) production systems requiring a least possible number of operators, causing the loss of many jobs. This has happened, for example, in many steelworks.
On the other hand, computers do create jobs. They are more skilled and better paid, though fewer in number than those they replace. Many activities could not continue in their present form without computers, no matter how many people are employed. Examples are the check clearing (交换) system of major banks and the weather forecasting system.
When a firm introduces computers, a few people are usually employed in key posts (such as jobs of operations managers) while other staff are re-trained as operators, programmers, and data preparation staff. After the new system has settled down, people in non-computer jobs are not always replaced when t
A. the possible widespread unemployment caused by their introduction
B. their use as part of automated production systems
C. the least possible number of operators
D. the production system in steelworks