How many total doughnuts did she buy? PLS HELP ME ITS DUE IN A HOUR

Aregression was run to determine if there is a relationship between hours of tv watched per day (x) and number of situps a person can do (y). the results of the regression were: y=ax+b a=-0.662 b=30.418 r2=0.703921 r=-0.839

What could explain what happened when the time was equal to 120 minutes

For the equations below which statement is true ?