The quantum theory of energy levels within atoms was alded by:
study of the sun's light spectrum
o emission line spectra of various elements
alpha particles
o gamma rays

Explanation:

The quantum theory of energy levels within atoms was aided by the emission spectrum. When excited with light, different elements emitted photons of different frequencies. The frequencies were different because the energy difference from excited to low energy state was different depending on the element.

Hope this helps :)

the cell theory states that all living things including animals, as well as plants, are made of cells.