OG理的问题

NKtkdlover

这道题怎末读不懂亚？顺便问一下，11th的数学变化大吗？

13. For a light that has an intensity of 60

candles at its source, the intensity in

candles, S, of the light at a point d feet

from the source is given by the

formula S = 60k/d*d, where k is a

constant. If the intensity of the light is

30 candles at a distance of 2 feet from

the source, what is the intensity of the

light at a distance of 20 feet from the

source?

(A) candle

3/10

(B) candle

1/2

(C) candles

4/3

(D) 2 candles

(E) 3 candles

Youknowme

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