A random sample of 29 observations is used to estimate the population mean. The sample mean...

A random sample of 29 observations is used to estimate the population mean. The sample mean and the sample standard deviation are calculated as 130.2 and 29.60, respectively. Assume that the population is normally distributed

Construct the 95% confidence interval for the population mean.

Construct the 99% confidence interval for the population mean

Use your answers to discuss the impact of the confidence level on the width of the interval.

As the confidence level increases, the interval becomes wider.
As the confidence level increases, the interval becomes narrower.

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