尽头线计算容车数是按其有效长减去()安全距离来计算的。
A.10m
B.15m
C.20m
D.25m
参考答案:A
---I’m fed up with studying.
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A.content is better than riches
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C.the world is your oyster
D.well begun is half done
某太阳能热水器的水箱内装有50kg的水,太阳光照射一段时间后,水温从20℃升高到60℃.水的比热容是c水=4.2×103J/(kg•℃).试求:
(1)水的温度变化△t是多少℃?
(2)水吸收的热量是多少焦耳?