Motion of a satellite: orbital velocity, time period and energy

The minimum energy required to launch a satellite of mass \(m\) from the surface of earth of mass \(M\) and radius \(R\) in a circular orbit at an altitude of \(2R\) from the surface of the earth is:

A satellite is orbiting just above the surface of the earth with period \(T\). If \(d\) is the density of the earth and \(G\) is the universal constant of gravitation, the quantity \(\frac{3\pi}{Gd}\) represents :

A satellite of mass \(m\) is orbiting the earth (of radius \(R\)) at a height \(h\) from its surface. The total energy of the satellite in terms of \(g_0\), the value of acceleration due to gravity at the earth's surface, is