Calculate the 99 confidence interval for the true

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2)Calculate the 99% confidence interval for the true population mean for the BMIdata. Recall that the new sample contains 15 people and has a mean of 25.97kg/m2and a standard deviation of 7.10 kg/m2.Because our sample has fewer than 30 cases, we cannot assume that the distribution ofsample means will be normal, and must use the t-distribution. The margin of error isbased on the significance level (1-confidence level, or 1-0.99=0.01), the standarddeviation (in B2) and the sample size (in B3).We can compute the margin of error usingthe Excel function CONFIDENCE.T(0.01,B2,B3). The lower bound of the 99%confidence interval is the sample mean minus the margin of error, that is B1–CONFIDENCE.T(0.01,B2,B3)= 25.97-5.46=20.51. The upper bound of the 99%confidence interval is the sample mean plus the margin of error, that isB1+CONFIDENCE.T(0.01,B2,B3)= 25.97+5.46=31.43. We can be 99% confident thatthe true mean BMI of all U.S. citizens is between 20.51 kg/m2and 31.43 kg/m2. You mustlink directly to cells to obtain the correct answer.
3)Calculate the 80% confidence interval for the true population mean based on asample withx¯=225, s=8.5, and n=45.

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