My data for 5 different screen times are 12 hours, 26 hours, 36 hours, 42 hours, and 55 hours. I need to use either statcrunch,excel or TI83/84 calculator to create a confidence interval. I must state which one I used and why? And why did I select a t or z distribution function. I must use a 95% confidence level and what is the confidence level? It has to include the point estimate for the population mean and the units. I have to have the margin of error and the units as well. It states suppose I knew that the population standard deviation for Americans scree time will be 4 hours. I also have to do it within a margin of error 0.25 hours. Asking how many Americans would I have to survey with the continue use of a 95% confidence level . I have to state in 2 ways how my info can be biased skewing my result.

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