The woodland paper company produces paper for the newspaper industry. As a final step in the process, the paper passes through a machine that measures various product quality characteristics when the paper production process is in control it averages $20$ defects per roll.a$)$ Set up control chart for the number of defects per roll use $2$ sigma control limits$.$b$)$ Five rolls had the following number of defects: $16,21,17,22,21$ and $24$ respectively.The sixth roll using pulp from a different supplier had $5$ defects. Is the paper production process is control?