They all have different compositions of protons, neutrons, and electrons. This causes variety and makes atoms different so they can make up different substances
If your asking where Most people in cities get there water.
Then the answer is by delivery through pipes.
Mass..... mass measures the amount of matter in a substance or object
The statement that describes the difference between the 2 isotopes of nitrogen would be the last set.
Nitrogen-14 has 7 electrons, 7 protons, and 7 neutrons
Nitrogen-15 has 7 electrons, 7 protons, and 8 neutrons.
