For each month from February to August, compare consumption with the previous month using the graph.

• Bonus (+$15): month where consumption drops more than 15% from the previous month.
• Penalty (-$15): month where consumption rises more than 30% from the previous month.
• Count the number of bonus months and penalty months separately.
• Net = (Bonus months × $15) − (Penalty months × $15).

Final Answer: $15