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问下狗主:小孩从童车里摔出来 已经整理了,我选的也是父母在政府的政策前已经知道有危险 问的是加强
这个题目你说已经整理出来了,可否帮忙看看是哪一个?
另第三题:CPT(Y一种节能灯)比日光灯好,貌似是日光灯,能的时间长,LED比CPT更好,但价格是CPT的五倍 问结论是什么。是不是og里面的这个:
Traverton’s city council wants to minimize the city’s average yearly expenditures on its traffic signal lights and so is considering replacing the incandescent bulbs currently in use with arrays of light-emitting diodes (LEDs) as the incandescent bulbs burn out. Compared to incandescent bulbs, LED arrays consume significantly less energy and cost no more to purchase. Moreover, the costs associated with the conversion of existing fixtures so as to accept LED arrays would be minimal.
Which of the following would it be most useful to know in determining whether switching to LED arrays would be likely to help minimize Traverton’s yearly maintenance costs? |
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