The mass of a planet is half that of the earth and the radius of the planet is one- fourth that of earth. If we plan to send an artificial satellite from the planet, the escape velocity will be , (escape velocity on earth $v_e=11\;km- s^{-1}$)

Question

$$\begin {array} {1 1} (a)\;11\; km-s^{-1} & \quad (b)\;5.5 \;km-s^{-1} \\ (c)\;15.55 \;km.s^{-1} & \quad (d)\;7.78\;km -s^{-1} \end {array}$$