the following table shows the test scores and sleep averages of several students. hours of sleep (x) 7 7 7 6 8 8 9 5 6 7 7 9 8 8 10 8 test score (y) 90 75 70 70 85 95 90 60 65 80 70 85 85 100 95 90 (a) use graphing technology (ti calculator or desmos) to find the linear regression equation that models the data. let x equal the hours of sleep and y equal test score. explain the steps you use. (b) use the equation to determine the approximate test score of a student who sleeps an average of 7.5 hours a night. show your work

Use the given degree of confidence and sample data to construct a confidence interval for the population mean mu . assume that the population has a normal distribution. a laboratory tested twelve chicken eggs and found that the mean amount of cholesterol was 185 milligrams with sequals 17.6 milligrams. a confidence interval of 173.8 mgless than muless than 196.2 mg is constructed for the true mean cholesterol content of all such eggs. it was assumed that the population has a normal distribution. what confidence level does this interval represent?