A library wants to determine if there is a difference in the prices charged by two local bookstores for any new books that were published this year. They sample prices from both companies. Test at a 0.05 level of significance if there is a difference in the prices. oo Mean cost of new books [$34.5 [$31.5 Sample standard deviation 1. State the letter of the correct null hypothesis and alternative hypothesis A. Ho: pa= pb Ha: pa # pb B. Ho: pa>= pb Ha: pa # pb C. Ho: pa pb D.Ho: pa=0Ha: ub #0