A hard$-$bake process is used in conjunction with photolithography in semiconductor manufacturing. Twenty$-$five samples of size five have been taken when we think the process is in control. The interval of time between samples or subgroups is one hour. The $x$ Dbar for all samples is $1\mathrm{.}51$ and the RBar $(\frac{?}{\text{b}\text{a}\text{r}}(R))$ is $0\mathrm{.}35.$ The specification limits on flow width are $1\mathrm{.}750+-0\mathrm{.}750$ microns. What is the $C_{pl}$ value for this process?

$1\mathrm{.}129$

None of these

$1,470$

$2\mathrm{.}19$

$1\mathrm{.}661$