Your skin has 3 layers. The top layer is called the epidermis. The middle layer is called the dermis. The bottom layer is called the subcutaneous fat.
Chlorine-the chemical element of atomic number 17, a toxic, irritant, pale green gas
atomic number-the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.
Carbon dioxide is what humans exhale, giving trees carbon dioxide will produce oxygen
