A body of mass m is situated at a distance 4Re. above the earth's surface, where Re is the radius of earth. How much minimum energy be given to the body so that it may escape

Potential energy of the body at a distance 4Re from the surface of earthU=−mgRe1+h/Re=−mgRe1+4=−mgRe5[As h = 4Re (given)]So minimum energy required to escape the body will be mgRe5.