4. A researcher has constructed an 80% confidence interval of 45  8, using a sample of n 25 scores.

a. What would happen to the width of the interval if the researcher had used a larger sample size?

(Assume other factors are held constant.)

b. What would happen to the width of the interval if the researcher had used 90% confidence instead of 80%?

c. What would happen to the width of the interval if the sample variance increased? (Assume other factors are held constant.)