1. If the mean of the sampling distribution of the mean is 6.5, which of the following statements best describe the population mean? *

A. The population decreases by 6.5.

B. The population mean and mean of the sampling distribution of the means cannot be compared.

C. The population mean is also equal to 6.5.

D. The population is greater than 6.5.

2. It is the value on the t distribution whose left tail probability is 93% and whose right-tail probability is 7%.

A. 93rd percentile

B. 7th percentile

C. right t-value

D. left t-value

3. For a 95% confidence level, the confidence coefficient is ____? *

A. 2.58

B. 1.96

C. 2.33

D. 1.645

4. The following statements tell about the t-distribution EXCEPT _________________

A. The t-distribution has thicker tails than the normal distribution.

B. The exact shape of a t-distribution depends on the degrees of freedom.

C. The standard deviation of the t-distribution is equal to 1.

D. As the degrees of freedom increase, the t-distribution tends to normal distribution.

5. What is the 95th percentile of the t-distribution if the sample size is 15? *

A. 1.771

B. 1.753

C. 1.345

D. 1.761

6. Using the t-table, if the t-value is -1.708 and the shaded region is on the left of the t-distribution, what is the area of the unshaded region?

A. 0.95

B. 0.10

C. 0.05

D. 0.90