$7.$ Consider a system A which needs to execute the following sequence of instructions:

lw $t$1,0($$t$2)$

sw $t$1,4($$t$3)$

lw $t$2,4($$t$3)$

addi $t$1,$ $t$1,4$

add $t$1,$ $t$3,$ $$0$

or $t$3,$ $t$1,$ $t$2$

sw $t$3,4($$t$1)$

a$.$ Assume $5-$stage pipelining and no forwarding mechanism. If each stage takes

$1$ clock cycle to complete, calculate with execution time $($in cycles$)$ for the

completion of whole program. Determine how many times the processor stalls

and how long is each stalls $($in terms of clock cycles$).$