Consider processors P$1,$ P$2$ and P$3$ executing the same instruction set. P$1$ has a

$2\mathrm{.}8$GHZ clock rate and a CPI of $1\mathrm{.}4.$ P$2$ has a $2\mathrm{.}5$GHZ clock rate and a CPI of $1\mathrm{.}2.$ P$3$ has a

$4\mathrm{.}0$GHZ clock rate and a CPI of $2.(1$ point each subquestion$)$

a$.$ Which processor has the highest performance in terms of $$instructions$/$sec$?$

b$.$ If the processors each execute a program in $12$sec$,$ find the number of cycles and the

number of instructions.

c$.$ We are trying to reduce the execution time by $30\%$ by increasing the clock rate on P$1.$

But this will lead to an increase in CPI by $20\%.$ What clock rate should we have to get

this time reduction for P$1$