$($a$)$What changes will need to be made to the program counter $($pc$)?$ Why?

$($b$)$Currently$,$ the instruction format is $12$ bits: four bits for the opcode, two bits for the source register, two bits for the destination register, and four bits for the immediate. What changes will be needed to the instruction format? Why? Consider all instructions in your answer.

$($c$)$What changes will need to be made to the general$-$purpose registers $($Rg$0..$Rg$3)?$ Why?

$($d$)$What changes will be needed to the instruction store $($myROM$)?$ Why? Consider both dimensions of the array.

$($e$)$Currently$,$ both ALUs use $4-$bit inputs and a $4-$bit output. What changes will be needed to the ALUs? Why?