The scatter plot shows the time spent studying compared to test scores for Mr. Stone’s eighth-grade class. What does the y-intercept represent?

A scatterplot with Time spent studying in hours on the X axis and test scores on the Y axis. There are several dots plotted close together that follow a fairly diagonal path that rises from left to right, along with the line Y equals 4.5 X plus 48 plotted through the approximate center of the points.

the test score when studying Choose... hours