The fission of a certain radioactive nucleus is accompanied by the release of 6.5 x 10¹¹J of energy. Calculate its mass defect.[c = 3.0 x 10⁸ms^-1]

• A.4.6 x 10^-20kg
• B.7.1 x 10^-16kg
• C.7.2 x 10^-8kg
• D.4.6 x 10^-4kg