A purchasing agent at the kelly bread company wants to estimate the

A purchasing agent at the Kelly Bread Company wants to estimate the mean daily usage of rye flour. She takes a sample for 50 straight days and finds that the sample mean is 180 pounds with a sample standard deviation of 38.5 pounds.
a.) State the 90% confidence interval for the mean (Round to hundredths)
b.) State the margin of error (Round to Tenths)
** Must show T1-83/84 Calculator function used and what numbers were typed in to arrive at answer 
** Must show problem using a formula, please type out formula and the number’s you used for that formula