Question $1$: A program with $520M$ instructions is run on two different processors, CPU$1$ anc CPU$2$ with the following specifications:

CPU$1$ specifications: $4\mathrm{.}6GHz$ clock and a CPI of $1\mathrm{.}8$

CPU$2$ specifications: $5\mathrm{.}2GHz$ clock and a CPI of $1\mathrm{.}3$

$($a$)$ How fast is CPU$1$ when compared to CPU$2$ while executing the above program? $(5$ points$)$

$($b$)$ A designer decides to reduce the execution time of the program by $12\%,$ by modifying the ISA. But the average CPI is increased by $18\%.$ Thus, this requires a change in the clock rate. What clock rate is required on each of the CPUs to achieve this? $(15$ points$)$