a. The correlation is a positive linear relationship.
b. The predicted grade for a student who studied for 3 hours is around 77.
a. The correlation can be described as a positive linear relationship. As the time spent studying increases, the grade also increases. This can be seen by looking at the data points on the scatter plot.
b. To predict the grade of a student who studied for 3 hours, we can use the regression line. Based on the data and the regression line, we can estimate that the grade would be around 77.