A: We say that it takes 500 to thousands of years to create an inch of topsoil. The reason is that soil is often derived from rock. The rock has to be broken into small pieces first. This happens by physical weathering: things like freezing and thawing in colder climates, and chemical weathering in warmer climates.
the answer is a because if the model is based on experimental data it wont be good unless it has been tested.
Explanation: An atom a fundamental piece of matter. ... An atom itself is made up of three tiny kinds of particles called subatomic particles: protons, neutrons, and electrons.
I believe the answer is A