● Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane , but commonly including varying amounts of otherhigher alkanes, and sometimes a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium. Hence, Statement 1 is correct . ◦ It is formed when layers of decomposing plant and animal matter are exposed to intense heat and pressure under the surface of the Earth over millions of years. ● Natural gas is a non-renewable hydrocarbon used as a source of energy for heating, cooking, and electricity generation. Hence, Statement 2 is correct . ◦ It is also used as a fuel for vehicles and as a chemical feedstock in the manufacture of plastics and other commercially important organic chemicals. ● Natural gas has an effect on climate change; it is a greenhouse gas itself, and creates carbon dioxide during oxidation. ◦ Natural gas can be used in place of coal , for example, to generate electricity, which may lower net carbon dioxide emissions in absence of carbon capture. Hence, Statement 3 is correct .