本人英语很差,现有一问题,望赐教

题目

本人英语很差,现有一问题,望赐教
在课本里有这么两句话：Since natural radiation is estimated to cause about 1% of all cancers,radiation due to nuclear technology should eventually increase our cancer risk by 0.002%(one part in 50000),reducing our life expectancy by less than one hour.By comparison,our loss of life expectancy from competitive electricity generation technologies ,buring coal,oil,or gas,is estimated to range from 3 to 40 days.第一句前面勉强能看懂,但是最后‘reducing our life expectancy by less than one hour’怎么也想不通什么意思,按照我的理解就成了“在不到一小时内减少了我们的预期寿命”,与前面联系一下,感觉这话说不通吧?在第二句By comparison,our loss of life expectancy from competitive electricity generation technologies ,buring coal,oil,or gas,is estimated to range from 3 to 40 days中,“from competitive electricity generation technologies ,buring coal,oil,or gas”在句中应该如何理解?又该如何翻译?

答案

Since natural radiation is estimated to cause about 1% of all cancers,radiation due to nuclear technology should eventually increase our cancer risk by 0.002%(one part in 50000),reducing our life expectancy by less than one hour.先分析句,三个小分句.第3个是补充说明的意思,而第1和第2带有对比的意味.

By comparison,our loss of life expectancy from competitive electricity generation technologies ,buring coal,oil,or gas,is estimated to range from 3 to 40 days.相比较之下,这几种方法的发电会使我们的寿命缩短3至40日不等.