This is Statistics. Answer what is required. Provide clean and clear solutions.

For items 13-15, use the problem below. The average score in the entrance examination in Mathematics at SRNHS is 80 with a standard deviation of 10. A random sample of 40 students taken from this year's examinees and it was found the mean score of 84. The level of significance is 0.05. 13. Which of these are the critical values? A. + 1.96 B. +1.97 C. $ 1.98 D. + 1.99 14. Using the Z- test formula, what is the computed test-statistic? A. 2.50 B. 2.51 C. 2.52 D. 2.53 15. Which is the appropriate conclusion about the hypothesized and the sample mean? A. The hypothesized mean is greater than the sample mean. B. There is no relationship between the hypothesized and the sample mean. C. There is significant difference between the hypothesized mean and the sample mean. D. There is no significant difference between the hypothesized mean and the sample mean