assume a world population of 8 billion and a u.s. population of 338 million. a. look up the present (2020 or 2021) total annual u.s. primary energy consumption. then determine the total world energy consumption in quads if the rest of the world were to use the same per capita energy as in the united states. b. if the energy source mix were to remain the same as the present mix in achieving the scenario of part a, what would be the percentage increase in co2 emissions?