The water cycle describes how water evaporates from the surface of the earth, rises into the atmosphere, cools and condenses into rain or snow in clouds, and falls again to the surface as precipitation. ... The cycling of water in and out of the atmosphere is a significant aspect of the weather patterns on Earth.
C)crabon,oxygen and calcium
Answer: 
Explanation:
Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products formed must be equal to the mass of reactants taken. In order to get the same mass on both sides, the atoms of each element must be balanced on both sides of the chemical equation.
The balanced combustion reaction is,:

1.regulating ph
2.heating
3.adding some oppositely charged colloids
U need positive and negative electordoe and an electrolyte <span />