Problem $7\mathrm{.}21(10$ points$)$ Consider two p$+$n silicon junctions at T $=300$ K reverse biased at VR $=5$ V$.$ The impurity doping concentrations in junction A are Na $=1018$ cm$3$ and Nd $=1015$ cm$3,$ and those in junction B are Na $=1018$ cm$3$ and Nd $=1016$ cm$3.$ Calculate the ratio of the following parameters for junction A to junction B: $($a$)$ W$,($b$)|$Emax$|,$ and $($c$)$ Cj $\text{'}$