For $4$bit number $($A$=$a$3,$ a$2,$ a$1,$ a$0,$ B$=$b$3,$ b$2,$ b$1,$ b$0,$ c$0)$

$1)$ For Full Adder logic $($ai$+$bi$+$ci$=$Si$...$Ci$+1),$ write equations for Si and Ci$+1$

$2)$ Write Carru LookAhead Generator$($CLAG$)$ equation for C$1,$ C$2,$ C$3,$ C$4$ in OR$-$AND form and implement the logic with all NOR logic, $($use Pi$=$Ai$$Bi$,$ Gi$=$AiBi$)$

$3)$ use CLAG block for $($A$+$B$)$ adder implementation.