What is the best interpretation
of the slope of the line?

A student's test score is likely to
increase about 20 points for each
hour spent studying.
Mr. Crawford's 4th-Period
Math Class

A student's test score is likely to
decrease about 1 point for every
30 minutes spent studying.
Test Scores

A student's test score is likely to
increase about 1 point for every
20 minutes spent studying.

A student's test score is likely to
decrease about 20 points for each
hour spent studying.