I think all organisms are made up of one or more cells and cells are the basic units of life and all cells arise from pre-existing cells.
Answer:

Explanation:
Skin covers all the body surfaces. The purpose of the skin is protect the body against infection, injury, heat or cold and also to store water and vitamins.
Body surface area is measure of surface area of the human body. It is measured in
.
<u>There are many ways to measure the skin surface area of the body but the formula which is widely used is Mosteller formula, which is:</u>

The primary succession takes a long time to be done. the secondary succesion takes 200-500 years for completion. the secondary succession occurs in an area which has been denuded recently and lately inhabited. soil is present at the beginning of the secondary succession with some organisms. thank you for this question.
A X-rays I think this is the answer