Problem $7\mathrm{.}53$

The data in Table $7$E$\mathrm{.}15$ represent the number of nonconformities per $1,000$ meters in telephone cable. From analysis of these data, would you conclude that the process is in statistical control? What control procedure would you recommend for future production? Follow your recommendation and show your work. Create revised control chart$($s$)$ based on your recommendation.