The Government of Ontario has introduced a new fixed electricity price of 12.8 ¢/kWh for customers that are on time-of-use (TOU) prices. Starting June 1, 2020, that price applies to electricity used at all hours of the day, seven days a week. A TV uses a 100W adapter when it is plugged in. How much would it cost to run the TV for 6 months 24 hours per day? Round to nearest whole number

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You're asking in the ap section, so i'll give the ap calculus-style answer. alternatively, you can find the vertex of the parabola and use the "y"-coordinate as the answer.

the maximum height can occur at a critical number, that is, a number  such that  .

the derivative of  can be calculated as follows:



find a value of  that is a zero of the derivative:


this is parabola that is opening downward; we can assume there is a maximum at  .

to find that maximum, calculate  .