Use the constant voltage drop model for the diode $($VD $=0\mathrm{.}6$V$)$ to find:

$($a$)$ Find the currents $1,2,2,$ and the voltage $3$ assuming $2=3[20$ Pts$]$

$($b$)$ Find the currents $1,2,2,$ and the voltage $3$ assuming $2=7[15$ Pts$]$

$($c$)$ Find $3$ for $2=0,$ using the exponential model $(=21016,=25)[15$ Pts