A random sample of 81 eighth grade? students' scores on a national mathematics assessment test has a mean score of 291. This test result prompts a state school administrator to declare that the mean score for the? state's eighth graders on this exam is more than 285. Assume that the population standard deviation is 40. At α=0.04?, is there enough evidence to support the? administrator's claim?
A.) Find the standardized test statistic z, and its corresponding area. z=_____(round to two decimal points)
B.) Find the P-Value. P-value=_____(round to three decimal points)
C.) Decide whether to reject or fail to reject.