$A$ rocket is launched normal to the surface of the Earth,away from the Sun,along the line joining the Sun and the Earth. The Sun is $3 \times 10^5$ times heavier than the Earth and is at a distance $2.5 \times 10^4$ times larger than the radius of the Earth. The escape velocity from the Earth's gravitational field is $v_e = 11.2 \text{ km s}^{-1}$. The minimum initial velocity $(v_s)$ required for the rocket to be able to leave the Sun-Earth system is closest to:
(Ignore the rotation and revolution of the Earth and the presence of any other planet)

• A
  $v_s = 22 \text{ km s}^{-1}$
• B
  $v_s = 42 \text{ km s}^{-1}$
• C
  $v_s = 62 \text{ km s}^{-1}$
• D
  $v_s = 72 \text{ km s}^{-1}$