Where does most of the mass of trees come from

The mass of a tree is primarily carbon. The carbon comes from carbon dioxide used during photosynthesis. During photosynthesis, plants convert the sun's energy into chemical energy which is captured within the bonds of carbon molecules built from atmospheric carbon dioxide and water.

it would affect precipitation by causing flooding in some areas of the world due to climate increasing, causing the glaciers in the northern and southern pole of our planet to melt.

i wish you would have provided choices to simplify it and allow me to give an exact answer.

this age may represent the age of the earth's accretion, of core formation, or of the material from which the earth formed. this dating is based on evidence from radiometric age-dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar samples.