1. Which statement is TRUE regarding statistical significance when looking at a 5% significance level?

a) Z-scores that fall within 2 standard deviations of the mean indicate statistical significance.

b) Statistical significance indicates that the null hypothesis should not be rejected.

c) A statistically significant result means that the null hypothesis should be rejected.

d) Z-scores that fall within 1 standard deviation of the mean indicate significant statistical significance.

2. A distribution of sample means has a mean of 150, with a standard distribution of 10. Assuming a normal distribution, which sample mean would be least likely to be chosen at random from the population of sample means?

a) 142

b) 155

c)134

d) 158

3. Which statement is TRUE regarding Type I and Type II errors?

a) Significant results indicate both Type I and Type II error.

b) A significant result coupled with a false null hypothesis is a Type I error.

c) Not getting significant result when the null hypothesis should be rejected is a Type II error.

d) Getting a significant result when the null hypothesis is true is a Type II error.

4. Which statement correctly defines a confidence interval?

a) A confidence interval is used to calculate the exact population mean.

b) A confidence interval indicates the range of values by giving just the z-score.

c) A confidence interval is equal to a sample mean plus or minus a margin of error.

d) A confidence interval calculates the range of values below a sample mean.

5. If the 95% confidence interval for a samplemean is 12 to 20, then:

a) you would be unlikely to find a sample mean greater than 20 if you took another sample.

b) the population mean must be between 12 and 20.

c) the population mean must be 16.

d) you would be likely to find a sample mean less than 12 if you took another sample.