Please solve this and please be organized

Problem 2 [10 points = 3 + 7] A group of n = 25 students was selected at random for studies related to the amount of time they spent for exam preparations. Educators assume that individual records are normally distributed with entirely unknown parameters (u, ). Sample summaries (in minutes per week) were obtained as Sample Mean = X = 90 and Sample SD = s = 20 Set confidence level as C = 0.95 1. What critical value are you going to use for estimation of population mean ? 2. Show all elements of your interval, including mid-point, margin of error, and confidence limits. You can leave answers in the form (UCL, LCL) = (Mid-Point) + (Margin of Error) Solution