An article reported that for a sample of 58 kitchens with gas cooking appliances monitored during a one-week period, the sample mean co2 level (ppm) was 654.16, and the sample standard deviation was 165.4.

(a) calculate and interpret a 95% (two-sided) confidence interval for true average co2 level in the population of all homes from which the sample was selected. (round your answers to two decimal places.) , ppm interpret the resulting interval. we are 95% confident that the true population mean lies below this interval. we are 95% confident that this interval does not contain the true population mean. we are 95% confident that this interval contains the true population mean. we are 95% confident that the true population mean lies above this interval.
(b) suppose the investigators had made a rough guess of 184 for the value of s before collecting data. what sample size would be necessary to obtain an interval width of 47 ppm for a confidence level of 95%?