Morton and Paul are members of different video game libraries. 
 Morton pays a $90 membership fee and $4 for each video game he rents. 
 The following function shows the total amount of money, y, in dollars, that Paul pays for renting x number of video games:
 y = 2x + 60.
 How many more dollars does Morton pay for a membership fee than Paul?
 $2
 $4
 $30
 $56