At the Thanksgiving break, I measured the correlation between the pre-class quiz grade and the average grade in the class for all 33 students in my stats classes. Below is the output from those...

At the Thanksgiving break, I measured the correlation between the pre-class quiz grade and the average grade in the class for all 33 students in my stats classes. Below is the output from those results.

Correlation

Pearson correlation of PreClass and Grade = 0.705630

P-Value = <>

Regression Equation

Grade = 0.24333 + 0.006369 PreClass

(a) Determine the critical value in the table and explain how you know these two variables would be considered correlated.

(b) Knowing that there is correlation, use this model to predict the average grade of a student in this class who did not complete any pre-class quizzes.

(c) Assuming everyone in this class completed at least one quiz, would you describe the previous problem as interpolation or extrapolation?