Use the following information to answer questions 30-32.

Data for each of 10 students is represented by a corresponding data point plotted in the standard (x, y)coordinate plane below. Each point has 2integer coordinates. The x-coordinate is the number of hours the student spent studying for a retake test, and the y-coordinate is the change in score from the original test to the retake test. Noel drew the line shown through 2 data points to help predict future changes in score.