M5I, A0V, A5V, and G9III A11. Star A appears brighter than star B, as seen from Earth. In a spectroscopic binary, the orbital motion of the component stars appears as variations in their radial velocities. When the Sun begins to evolve to become a red giant, a. Once on the main sequence, gravity is no longer important in determining a star's internal structure.
Stars are spherical because of a. the high temperature in the interior.
Show all work. A red giant's size is that of a. the Sun b. the Earth c. A white dwarf's size is that of a. the Sun b. the Earth c. Their hydrogen fuses faster because of greater pressure. There is less hydrogen in their cores.