The mass of a spaceship is 1000 kg. It is to be launched from the earth’s surface out into free space. The value of ‘g’ and ‘R’ (radius of the earth) is 10 m/s2 and 6400 km respectively. The required energy for this work will be
(a) 6.4 x 1010 Joules
(b) 6.4 x 1011 Joules
(c) 6.4 x 108 Joules
(d) 6.4 x 109 Joules