A ball of mass 0.2 kg rests on a vertical post of height 5m. A bullet of mass 0.01 kg, travelling with a velocity v m/s in a horizontal direction, hits the centre of the ball. After the collision, the ball and ullet travel independently. The ball hits the ground at a distance of 20 m and the bullet at a distance of 100m from the foot of the post. the initial velocity v of the bullet is

Options

A. `250 m//s`
B. `250 sqrt2 m//s`
C. `400 m//s`
D. `500 m//s`