Assuming an average energy of 200 MeV per fission, calculate the number of fissions per second needed for a 500 megawatt reactor. (1MeV is 1.60 x 10^-13 Joules ) Assume (unrealistically) an efficiency of 100%.

1) 1.50 x 10²⁴ 

2) 1.56 x 10¹⁹  

3) 1.45 x 10²² 

4) 2.50  x 10⁶