b
Number of uranium atoms in \(2 kg\)

\(=\frac{2 \times 6.023 \times 10^{26}}{235}\)

energy from one atom is \(200 \times 10^{6}\) e.v. hence total energy from \(2 kg\) uranium

\(=\frac{2 \times 6.023 \times 10^{26}}{235} \times 200 \times 10^{6} \times 1.6 \times 10^{-19} J\)

\(2 kg\) uranium is used in \(30\) days hence this energy is recieved in 30 days hence energy recived per second or power is

Power \(=\frac{2 \times 6.023 \times 10^{26} \times 200 \times 10^{6} \times 1.6 \times 10^{-19}}{235 \times 30 \times 24 \times 3600}\)

Power \(=63.2 \times 10^{6}\) watt or \(63.2\) Mega Watt