Question

Please solve this question.
& don't spam.
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Answer 1

Answer:

Option B)

Step-by-step explanation:

Given

$r = \frac{f}{n + f}$

Therefore

R ( N+ F ) = F

RN + RF = F

RN = F - RF

RN = F ( 1 - R)

$f = \frac{ r \: n}{(1 - r)}$