The number of minutes first-graders spend on homework every day are normally distributed with a population standard deviation of 5 minutes and an unknown population mean. A random sample of 30 observations is taken and results in a sample mean of 36 minutes per day. Identify the parameters needed to calculate a confidence interval at the 95% confidence level. Then find the confidence interval. z0.10z0.05z0.025z0.01z0.0051.2821.6451.9602.3262.576 You may use a calculator or the common z values above. Round each number to three decimal places, if necessary.