Find the critical value t for the following situations. a) a 99% confidence interval based on df = 23 b) a 95% confidence interval based on df = 7 a) What is the critical value of t for a 99% confidence interval with df = 23? 2.81 (Round to two decimal places as needed.) b) What is the critical value of t for a 95% confidence interval with df = 7? 2.36 (Round to two decimal places as needed.)