20. The American Association of Advertising Agencies records data on nonprogram minutes on half-hour, prime-time television shows. Representative data in minutes for a sample of 20 prime-time shows on major networks at 8:30 p.m. follow. 6.0 6.6 5.8 7.0 6.3 6.2 7.2 5.7 6.4 7.0 6.5 6.2 6.0 6.5 7.2 7.3 7.6 6.8 6.0 6.2 Assume a normal population and provide a point estimate and a 95% confidence interval for the mean number of nonprogram minutes on half-hour, prime-time television shows at 8:30 p.m.