Please help me answer these review questions, thank you

1. The Quantization of electron energy states in an atom is better understood in terms of the electron's
A. wave nature.
B. neither of these.
C. particle nature.

2. A beam of electrons has
A. wave properties.
B. particle properties.
C. both of these.
D. neither of these.

3. Physics pioneers Balmer, Rydberg, and Ritz discovered in atomic spectra that electrons occupy well-defined shells about the atomic nucleus.
A. mathematical order.
B. that all atoms are essentially the same size.
C. that electrons behave as standing waves.
D. a randomness that opened the door to the nature of probabilities in atomic reality.

4. Compared to the average diameter of a hydrogen atom, the average diameter of a helium atom is
A. about the same.
B. smaller.
C. larger.

5. Orbital electrons do not spiral into the nucleus because of
A. electromagnetic forces.
B. the large nuclear size compared to the electron's size.
C. the wave nature of the electron.
D. none of these.
E. angular momentum conservation.

6. X-rays may be regarded as
A. none of these.
B. high frequency sound waves.
C. both of these.
D. high frequency radio waves.

7. An atom with an imbalance of electrons to protons is
A. a hadron.
B. none of these.
C. an isotope.
D. an ion.
E. a baryon.

8. The operation of a cloud chamber relies on
A. acceleration.
B. evaporation.
C. magnetization.
D. polarization.
E. condensation.

9. Pure elements can be transformed into entirely different elements. This statement at the present time is
A. false.
B. true.

10. Radioactivity in the world is something
A. relatively new.
B. as old as the world itself.