A ball is dropped from the top of a building .It takes 0.5 s to fall past the 3m length of a window some distance from the top of the building .If the velocity of the ball at the top and at the bottom of the window are `V_(T)` and `V_(B)` respectively then `V_(T)+V_(B)=?`

Explanation

`S=((u+v)/(2))t`
`3=(v_(T)+v_(B)/(2))0.5`
`V_(T)+V_(b)=12m//s`