a
Resistance, $R=\frac{V^{2}}{P}$
$\Rightarrow \quad R_{1}=\frac{(220)^{2}}{25}=1936 \,\Omega$
$R_{2}=\frac{(220)^{2}}{100}=484\, \Omega$
$\mathrm{i}=\frac{220}{\mathrm{R}_{1}+\mathrm{R}_{2}}=\frac{1}{11}\, \mathrm{A}$
Power dissipated through $\mathrm{R}_{1}=\mathrm{P}_{1}=\mathrm{i}^{2} \mathrm{R}_{1}=16\, \mathrm{W}$
Power dissipated through $\mathrm{R}_{2}=\mathrm{P}_{2}=\mathrm{i}^{2} \mathrm{R}_{2}=4 \,\mathrm{W}$
