Question

the brightness of a star when viewed from earth. actual brightness apparent magnitude absolute magnitude true luminosity a star of extremely high density composed entirely of neutrons. pulsar neutron star red supergiant quasar

Explanation:

1. The brightness of a star as seen from Earth is called apparent magnitude. It takes into account the star's actual luminosity and its distance from Earth. Actual brightness and true luminosity refer to the star's intrinsic brightness, and absolute magnitude is the apparent magnitude a star would have at a standard - distance.
2. A star of extremely high density composed entirely of neutrons is a neutron star. Pulsars are a type of neutron star that emit beams of electromagnetic radiation. Red supergiants are large, cool stars, and quasars are extremely luminous active galactic nuclei.

Answer:

1. B. apparent magnitude
2. B. neutron star