Correct Answer - D

Distance from `A to B = S = (1)/(2) ft_(1)^(2) rArr ft_(1)^(2) rArr ft_(1)^(2) = 2S `

Distance from ` B to C = (f_(1))t `

Distance from `C to D = (u^(2))/(2a) = ((ft_(1))^(2))/2(f//2) = ft_(1)^(2) = 2S`

`rArr S + f t_(1)t + 2 S = 15 S rArr f t_(1)t = 12 S `

But `1/2 f t_(1)^(2) = S `

On dividing the above two equations , we get `t_(1) = (t)/(6) `

`rArr S = 1/2 f (t/6)^(2) = (f t^(2))/(72) `