Formula used:\(v_0=\sqrt{Rg},v_e=\sqrt{2Rg}\)
Orbital velocity of a satellite revolving in a circular orbit at a height\((h< < R),v_0=\sqrt{Rg}\)
and the velocity required to escape is \(v_e=\sqrt{2Rg}\)
So increase in velocity,
\(\Delta v=v_e−v_0=(\sqrt2-1)\sqrt{Rg}\)
Final Answer: (a)