Please help for test

A student of journalism is curious about the average rates paid to freelancers by online magazines. She takes a random sample of 101 online publications and computes a mean rate per word of 13.5 cents, with a sample standard deviation of 5.3 cents. The student wants to use this sample information to find a 90% confidence interval for the average pay rate per word. Round all final answers to 3 decimal places. (a) What is the critical t-value that will need to be used to calculate the confidence interval? (b) What is the 90% confidence interval? :]