What is the melting point of a substance

depending on what it is for water it is 32°F

steel is 2500°F

aluminum 1,221°F

zinc is 787.2°F

sorry i cant put all the melting points

unless u mean  

Melting point, temperature at which the solid and liquid forms of a pure substance can exist in equilibrium. As heat is applied to a solid, its temperature will increase until the melting point is reached. More heat then will convert the solid into a liquid with no temperature change.

b. the carbon cycle ensures living things have a source of hydrogen