$3.(30$ points$)$ Given the positive number $77.$

a$)$ Represent the number as an eight$$bit number in two$$s$$complement form.

Also give the $2$ character hexadecimal value.

b$)$ Represent the negative number $77$ as an eight$$bit number in two$$s$$complement form.

Also give the $2$ character hexadecimal value.

c$)$ Add the binary result for a to b to verify you get an eight$-$bit value of zero!