(1)

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Energy of satellite on surface of earth,

$E_i=-\frac{GmM}{R}$

The energy at distance $(2R+R=3R),$

$E_f=\frac{-GMm}{2\left(3R\right)}=\frac{-GMm}{6R}$

Energy required to launch the satellite,

       $E=E_f-E_i=\frac{-GMm}{6R}-\left(\frac{-GMm}{R}\right)$

                              $=\frac{5GMm}{6R}$

(2)

Total energy of satellite at height $h$ from the earth's surface,

        $E=PE+KE=-\frac{GMm}{(R+h)}+\frac{1}{2}m{v}^2$                             ...(i)

Also, $\frac{m{v}^2}{(R+h)}=\frac{GMm}{{{\displaystyle (}{\displaystyle R}{\displaystyle +}{\displaystyle h}{\displaystyle )}}^2}$

or,    $v^2=\frac{GM}{R+h}$                                                                     ...(ii)

From eqns. (i) and (ii),

      $E=-\frac{GMm}{(R+h)}+\frac{1}{2}\frac{GMm}{(R+h)}=-\frac{1}{2}\frac{GMm}{(R+h)}$

          $=-\frac{1}{2}\frac{GM}{R^2}\times \frac{m{R}^2}{(R+h)}=-\frac{m{g}_0{R}^2}{2(R+h)}$