suppose we have two implementations of the same instruction set architecture. computer A has a clock rate of $4GHz$ and a $\frac{C}{P}$I of $4\mathrm{.}0$ for same program. computer $B$ has a clock rate of $5GHz$ and a $\frac{C}{P}$I of $2\mathrm{.}5$ for the same program.

computer $A$ is faster than computer $B$

computer $B$ is faster than computer $A$

both computers have the same execution time