`""^(226)Ra` disintegrates at such a rate that after 3160 years, only one fourth of its original amount remains . The half life of `""^(226)Ra` will be

Options

A. 790 years
B. 3160 years
C. 1580 years
D. 6230 years

Answer

C

Explanation

`(1)/(4)` th of the amount is left after 2 half lives
`therefore 2 xx t_(1//2)=3160` years
`therefore t_(1//2)=(3160)/(2)=1580`years.