You are tasked with evaluating if there is a difference in the average wages of college graduates and non-college graduates. You take a random sample of 1,600 college graduates and a random sample of 2,700 non-college graduates. The average wage in your sample of graduates is $35/hour, with a sample standard deviation of $40/hour. The average wage in your sample of non-graduates is $31/hour, with a standard deviation of $90/hour.

a. What are your null and alternative hypotheses?

b. State your conclusion regarding the difference in average wages, using 5% significance.

c. What is the 95% confidence interval for the difference in average wages?