1. Elements of the Periodic Table are distinguished by
(a) The number of protons in the nucleus.
(b) The number of neutrons in the nucleus.
(c) The number of electrons in the atom.
(d) Both (a) and (b).
(e) (a), (b), and (c).
2. A nucleus has
(a) More energy than its component neutrons and protons have.
(b) Less energy than its component neutrons and protons have.
(c) The same energy as its component neutrons and protons have.
(d) More energy than its component neutrons and protons have when the nucleus is at rest but less energy than when it is moving.