World energy supplies are often measured in the unit of quadrillion British thermal units (10^12 Btu ), generally called a "quad." In 2015, world energy consumption is projected to be 5.81x10^17 kJ . Current annual energy consumption in the United States is 99.2 quads. Assume that all this energy is to be generated by burning CH4(g) in the form of natural gas. If the combustion of the were complete and 100 % efficient, how many moles of CH4 would need to be combusted in order to provide the U.S. energy demand?