The current amplitude $I$ versus driving angular frequency $\omega_{d}$ for a driven $R L C$ circuit is given in Fig. $31-30,$ where the vertical axis scale is set by $I_{s}=4.00$ A. The inductance is $200 \mu \mathrm{H},$ and the emf amplitude is 8.0 $\mathrm{V} .$ What are $(\mathrm{a}) \mathrm{C}$ and ( b ) $R ?$