For parts a and b, use the t tables, software, or a calculator to estimate. For parts c and d, use software or a calculator to estimate. a) the critical value of t for a 95% confidence interval with df = 28. b) the critical value of t for a 99% confidence interval with of = 51. c) the P-value for t2 2.16 with 8 degrees of freedom. d) the P-value for |t| > 1.96 with 28 degrees of freedom. Click the icon to view the t table. a) What is the critical value of t for a 95% confidence interval with df = 28? (Round to two decimal places as needed.). b) What is the critical value of t for a 99% confidence interval with df = 51? (Round to two decimal places as needed.) c) What is the P-value for t2 2.16 with 8 degrees of freedom? (Round to three decimal places as needed.) d) What is the P-value for It| > 1.96 with 28 degrees of freedom? (Round to three decimal places as needed.)