The distance of a geostationary satellite from the surface of the Earth (radius $R_e = 6400 \ km$) in terms of $R_e$ is ....... (in $R_e$)

Two satellites,$A$ and $B,$ have masses $m$ and $2m$ respectively. $A$ is in a circular orbit of radius $R,$ and $B$ is in a circular orbit of radius $2R$ around the earth. The ratio of their kinetic energies,$K.E._A / K.E._B ,$ is

$A$ satellite of mass $M$ is in a circular orbit of radius $R$ about the center of the Earth. $A$ meteorite of the same mass $M$,falling towards the Earth,collides with the satellite completely inelastically. The speeds of the satellite and the meteorite are the same,just before the collision. The subsequent motion of the combined body will be:

$A$ planet of mass $m$ moves in an ellipse around the sun of mass $M_S$ such that its maximum and minimum distances are $r_1$ and $r_2$ respectively. The angular momentum of the planet relative to the center of the sun is

Which one of the following statements regarding an artificial satellite of the earth is incorrect?

Two stars of masses $M$ and $2M$ are at a distance $d$ apart and are revolving around their common center of mass. The angular velocity of the system of the two stars is ($G$ is the universal gravitational constant).