问题
单项选择题
制冷系统试运转时，应检查润滑油温度，一般不超过70℃，也不低于（）℃。
A.5
B.10
C.15
D.20
答案
参考答案：A
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制冷系统试运转时，应检查润滑油温度，一般不超过70℃，也不低于（）℃。
A.5
B.10
C.15
D.20
参考答案：A
| 阅读理解。 | |
| Read the following text and choose the most suitable heading from A-F for eachparagraph. There is one extra heading which you do not need.
1. ________________________ A world record is every athlete's dream, but the hard-won records of a few years ago are mostly just today's qualifying times. Roger Bannister's famous four-minute mile of 1956 has been beaten by nearly 15 seconds, while almost an hour and twenty minutes has been taken off the women's marathon since. 1953. 'Faster, higher, stronger', is the Olympic motto, and today's competitors continue to push back the boundaries of what the body can achieve. But one wonders if this can continue. 2. ________________________ The last forty years have seen many important technological advances. For example, since the introduction of strong flexible, fiberglass poles, over a meter has been added to the pole vault record. There have also been important developments in the design of the running shoe. And while a shoe won't actually make someone run faster, modern shoes do mean many more miles of comfortable, injury-free training. 3. ________________________ Pushing back the limits now depends more on science, technology and medicine than anything else. Athletic technique, training programmes and diets are all being studied to find ways of taking a few more seconds off or adding a few more centimetres to that elusive world record. It seems that natural ability and hard work are no longer enough. 4. ________________________ The research to find more efficient ways of moving goes on. Analysis of an athlete's style is particularly useful for events like jumping and throwing. Studies show that long jumpers need to concentrate not on the speed of approach, as once thought, but on the angle their bodies make with the ground as they take off. However, the rules governing each sport limit advances achieved by new styles. For instance only one-footed takeoffs are allowed in the high jump. 5. ________________________ In the future, it should be possible to develop a more individual approach to training programmes. Athletes will keep detailed diaries and collect data to help predict the point when training becomes overtraining, the cause of many injuries. If athletes feed all their information into a database, it may then be possible to predict patterns and to advise them individually when they should cut. |