If a substance with hlaf life `3` days is taken at other place in `12` days. What amount of substance is laft now ?

Options

A. `1//4`
B. `1//8`
C. `1//16`
D. `1//32`

Answer

C

Explanation

`T = t_(1//2) xx n` i.e., `12 = 3 xx n rArr n = 4`
`N = N_(0) ((1)/(2))^(n) rArr (N)/(N_(0)) = ((1)/(2))^(4) = (1)/(16)`