Use defect rate control chart to streamline payment procedures for insurance leavers to streamline payment procedures

Therefore, it is intended to be managed. To this end, a sample with a sample size of $200$ is collected every day, and the results collected for $20$ days are as follows.

$($a$)$ Calculate control limits to monitor future performance.

$($b$)$ What is the minimum sample size for a size greater than zero on the control lower limit on this defect rate control chart?