Specifications for a quality characteristic are $203\mathrm{.}3$ to $242\mathrm{.}5.$ Twenty$-$five $(25)$ subgroups of size n$-5$ are sampled and used to develop control charts for & and R$,$ which indicate a stable process with only common cause variation present. From these charts, $=223\mathrm{.}4$ and R $-13\mathrm{.}8,$ compute Opt