17. Circle the letter of each sentence that is true about the nuclear theory of atoms suggested by Rutherford's experimental results.
a. An atom is mostly empty space.
b. All the positive charge of an atom is concentrated
in a small central region called the nucleus.
c. The nucleus is composed of protons.
d. The nucleus is large compared with the atom as a whole.
e. Nearly all the mass of an atom is in its nucleus.