Name of locomotory and breathing organs of shark

Quickly what are the following of organisms that existed over a wide area but only for a limited time period called a.soft fossils b.mold fossils c.index fossils d.trace fossils

Describe the properties of sodium, chlorine, and sodium chloride

In chemistry, the type of an atom (what element it is) is determined by: a) the number of protons it contains in its nucleus.b) the number of neutrons it contains in its nucleus.c) the number of protons it has in a cloud around the nucleus.d) the number of neutrons it has in a cloud around the nucleus.e) the number of electrons it exchanges with its neighbors.