A car accelerating at the rate of 2 `m//s^2` from rest from origin is carrying a man at the rear end who has a gun in his hand. The car is always moving along positive x-axis. At `t=4` s, the man fires a bullet from the gun and the bullet hits a bird at `t=8`s. The bird has a position verctor `40hati + 80hatj + 40hatk`. Find velocity of projection of the bullet. Take the y-axis in the horizontal plane. `(g=10m//s^2)`.