From a ballon rising vertically upwards at 5 m/s, a stone is thrown up at 10 m/s relative to the balloon. Its velocity with respect to ground after 2 sec is - (assume g = 10 `m//s^(2)`)

Options

A. 0
B. 20 m/s
C. 10 m/s
D. 5 m/s

Answer

D