A store manager wants to investigate customer spending in his store. He randomly selects 30 customers and records their purchase total. He finds the mean to be $125 and the standard deviation to be $32. Construct and interpret a 95% confidence interval for the true mean purchase total for all customers. Use this table to determine the appropriate value of t*. Enter the degrees of freedom and the value of t* (exactly as you see it written in the table). Degrees of freedom = t* =