We have two implementation of the same instruction set architecture. Machine $"$A$"$ has a clock cycle time $($clock period$)$ of $1ns$ and CPI of $2\mathrm{.}0$ for some program. Machine $"$B$"$ has a clock cycle time of $2ns$ and CPI of $1\mathrm{.}2$ for the same. Which machine is faster for this program and by how much? Note: Execution Time cycles$/$instruction