Four main types of carbon-based molecules are found in living things. All organisms are made of four types of carbon-based molecules: carbohydrates, lipids, proteins, and nucleic acids. Fruits and grains both contain large amounts of carbohydrates. Carbohydrates are molecules made of carbon, hydro- gen, and oxygen.
Yes you can. The atomic mass measured from the proteins and neutrons in an atom, since you know he number of protons, you can subtract and be left with the number of neutrons.