Susan sells bottles of water at local sporting events. On a typical day, she sells 30 bottles for $1each. Today, she is trying out a special and is selling her bottles of water for only $0.50 each, andshe ends up selling 60 bottles.

The extra $15 she earns from selling the additional 30 bottles ofwater at $0.50 each is called __________.The $0.50 given back to the customers who wouldhave paid the normal $1.00 price is called __________.

• price effect; output effect
• output effect; price effect
• opportunity cost; price effect
• output effect;marginal revenue