COD Section $4\mathrm{.}4($A simple implementation scheme$)$ does not discuss l$-$type instructions like ADDI or ANDI

$($a$)$ What additional logic blocks, if any, are needed to add I$-$type instructions to the CPU shown in COD Figure $4\mathrm{.}23($The simple control

and datapath...$)?$ Add any necessary logic blocks to COD Figure $4\mathrm{.}23($The simple control and datapath...$)$ and explain their

purpose.

$($b$)$ List the values of the signals generated by the control unit for ADDI. Explain the reasoning for any "don't care" control signals.