A theory is an idea that has yet to be proven by experimentation. A law is a theory that has been proven correct.
The sun gets closer to the earth
Scientists did not know how traits were inherited.
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.