**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/s ^{2} and 6400 km respectively. The required energy for this work will be**

(a) 6.4 x 10^{10 }Joules

(b) 6.4 x 10^{11 }Joules

(c) 6.4 x 10^{8 }Joules

(d) 6.4 x 10^{9 }Joules