A Sample of N = 9 College Students Is Used

Multiple Choice

A sample of n = 9 college students is used to evaluate the effectiveness of a new Study Skills Workshop.Each student's grade point average (GPA) is recorded for the semester before the workshop and for the semester after the workshop.The average GPA improved by M_D = 0.60 points with s² = 0.09.The researcher would like to use the sample to estimate how much effect the workshop would have for the entire college population.Which of the following is the 80% confidence interval for these data?

A) µ_D = 0.60 + 0.01(1.397)
B) µ_D = 0.60 + 0.09(1.860)
C) µ_D = 0.60 + 0.10(1.397)
D) µ_D = 0.60 + 0.10(1.860)