Given are five observations for two variables, x and y. Use Table 2 of Appendix B. Xi 1 2 3 4 5 Yi 4 7 5 12 14 Round your answers to two decimal places. a. Using the following equation: S* = 8 n + (x * -x) Estimate the standard deviation of * when x = 4. b. Using the following expression: * ta/28* Develop a 95% confidence interval for the expected value of y when x = 4. to c. Using the following equation: 1 (x*x) Spred = s 1+ + n (; - )2 Estimate the standard deviation of an individual value of y when x = 4. d. Using the following expression: * ta/2 spred Develop a 95% prediction interval for y when x = 4. to