Q$3.$ For the below $4-$bit adder$/$ subtractor circuit perform the following operation

Addino$\frac{n}{s}$ubtraction

$A_4{A}_3{A}_2{A}_1$

$A={1011}_2,B={0111}_2$ and Mode control $=1$

$A={1011}_2,B={0111}_2$ and Mode control $=0$