In constructing a confidence interval for the population mean using the t-distribution, we often need the degrees of freedom (df), confidence level, and the critical value. Use the Student t-distribution to determine the missing values in the table below. Report the positive t critical value accurate to 3 decimal places. Sample Degrees of Confidence Critical size freedom level value (t) 23 1.321 26 90% 8 % 2.896 26 95%