Complete the following mcq:
Q1. A random sample of 10 observations is selected from the first normal population and 8 from the second normal population. For a one-tailed test of hypothesis (.01 significance level) to determine if there is a difference in the population means, the degrees of freedom are
A.18
B.17
C.16
D.None of the above
Q2. A random sample of 10 observations is selected from the first normal population and 8 from the second normal population. For a one-tailed test of hypothesis (.01significance level) to determine if there is a difference in the population means, the critical value(s) are
A. 2.552
B. -2.921 or 2.921
C. -2.583 or 2.583
D. None of the above
Q3. Which of the following is a requirement for a test of proportions?
A.The population standard deviations are equal.
B.Both populations are positively skewed.
C. Both samples are at least 30.
D. np and n (1-p) are both greater than 5.