Ground state energy = \( E_1 = -13.6 \, \text{eV} \)
Second excited state \( n = 3 \Rightarrow E_3 = -\frac{13.6}{9} = -1.51 \, \text{eV} \)
\[
\text{Energy required for (a)} = E_3 - E_1 = (-1.51) - (-13.6) = 12.09 \approx 12 \, \text{eV}
\]
\[
\text{Energy required for (b)} = 0 - (-13.6) = 13.6 \, \text{eV}
\]