Final answer:
In 2015, the United States produced 4 trillion kWh of electricity, with coal contributing 520 billion kWh, natural gas 1.24 trillion kWh, and petroleum 1.46 trillion kWh, based on their respective percentages of the total energy mix.
Step-by-step explanation:
The United States produced about 4 trillion kilowatt hours (kWh) of electricity in 2015.
According to provided data, the sources of energy can be broken down into percentages: 13% is coal, 31% is natural gas, and 36.5% is petroleum (oil).
We can calculate the amount of electricity produced by each source by multiplying the total production by the percentage for each source.
Multiply the total kWh by the percentage for coal: 0.13 × 4,000,000,000,000 kWh = 520,000,000,000 kWh.
Multiply the total kWh by the percentage for natural gas: 0.31 × 4,000,000,000,000 kWh = 1,240,000,000,000 kWh.
Multiply the total kWh by the percentage for petroleum: 0.365 × 4,000,000,000,000 kWh = 1,460,000,000,000 kWh.
Therefore, in 2015, coal produced 520 billion kWh, natural gas produced 1.24 trillion kWh, and petroleum produced 1.46 trillion kWh of electricity.