In 2018, U. S nuclear reactors generated 2.905x10^15 kJ of electrical energy (19.3% of the total electrical energy produced). One type of fuel used in electrical power plants is petroleum. Petroleum is composed of different rations of carbon-hydrogen compounds. One of those compounds is 1, 3-dimethylcyclochexane (C8H16).In 2018 liquid petroleum facilities generated .4% of the US electrical generation. Use combustion enthalpy to calculate the number of kilograms of C8H16 burned to generate the same amount of energy as the nuclear reactors.

Can someone me with questions 12 and 13 plz.

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.

Carbon-14 undergoes radioactive decay in the reaction above. determine the type of radiation emitted in this reaction and describe what is happening to the nucleus during this reaction.