The best way may be is going over the notes on the chapter you were doing. Or going over the chapter once or twice.
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.
C. because stimuli is how your body responds to something, and in this case, someone's heart rate increases WHEN their blood oxygen drop. Do you see how it responds? ;-)
