A Iandom sample ofn = 12 observations from a normal population produced ; = 47.9 and 52 = 4.5. Test the hypothesis H0: _u = 48 against Ha: y. at 48 at the 5% level of signicance. State the test statistic. [Round your answer to three decimal places.) State the rejection region. (If the test is onetailed, enter NONE for the unused region. Round your answers to three decimal places.) . 2 E . . E