Use the Harvard Classification Scheme (shown in the table above) to answer the following quesiton The Sun contains spectral lines from neutral sodium and calcium as well as ionized calcium magnesium a?

The Sun is classified as a G2V star according to the Harvard Classification Scheme. This indicates that it is a main sequence star with a surface temperature of around 5,500°C. The spectral lines from neutral sodium and calcium suggest the presence of these elements in the Sun's atmosphere, while the ionized calcium and magnesium lines indicate their presence in the outer layers of the Sun.