An abrupt Si p$-$n junction $($A $=10-4$ cm$2)$ has the following properties at $300$ K:

p side

n side

Na $=1017$ cm$-3$

Nd $=1015$ cm$-3$

n $=0\mathrm{.}1$s

p $=10$s

$$p $=200$ cm$2/$V$-$s

$$n $=1300$ cm$2/$V$-$s

$$n $=700$ cm$2/$V$-$s

$$p $=450$ cm$2/$V$-$s

$($a$)$ Calculate pn and np

$($b$)$ Calculate Dn and Dp

$($c$)$ The junction is forward biased by $0\mathrm{.}5$ V$.$ What is the current?

$($d$)$ What is the current at a reverse bias of $0\mathrm{.}5$ V$?$