An astronaut takes a ball of mass m from earth to space. He throws the ball into a circular orbit about earth at an altitude of 318.5 km. From…

An astronaut takes a ball of mass $\displaystyle m$ from earth to space. He throws the ball into a circular orbit about earth at an altitude of $\displaystyle 318.5$ km . From earth's surface to the orbit, the change in total mechanical energy of the ball is $\displaystyle x \frac{\mathrm{GM}_{\mathrm{e}} \mathrm{m}}{21 \mathrm{R}_{\mathrm{e}}}$. The value of $\displaystyle x$ is (take $\displaystyle \left.\mathrm{R}_{\mathrm{e}}=6370 \mathrm{~km}\right)$ :