No cursive and simple answer

12. A local school district claims that the average number of school days missed by its teachers due to illness is above the national average of 6. Write the null and alternative hypotheses which would be used to test this claim. You must show the parameters in your hypotheses. Ho : Ha : 13. If the sample size is 45 and the population standard deviation is unknown, what type of test should be used to test the statement in #12 above? Assume that all statistics needed for any calculation are available. a) T-test b) Z-test C ) 1-prop-z-test 14. A random sample of 85 students has a test score average of 79 with a standard deviation of 11.4. Find the margin of error for the 95% confidence interval. Margin of error is: 15. Complete the sentence: The smaller the calculated p-value, A) The lower the probability our calculations are correct B) The more evidence there is to reject H. C) The less evidence there is to reject H. 16. Given the same sample statistics and level of confidence, what effect does an increase in the standard deviation have on the width of a confidence interval? a) the width increases b) the width decreases c) there is no change 17. Compute the standardized test statistic to test the claim o = 34.4 if n =12, s = 28.8 and a = 0.05. a) 0.492 b) 12.961 c) 18.490 d) 9.209 18. In the problem above, what would be the correct decision? (Hint: sketch the rejection region) a) Reject HO b) Fail to reject HO