What happens to temperature when a star runs out of fuel

when hydrogen in the core is exhausted, the star begins hydrogen burning in a shell around the degenerate helium core while moving up the red giant branch. as the hydrogen fuel runs out, huge pressure raises the temperature to 100,000,000°, where helium burning is possible. Hope this helps. Mark me brainliest?:)

може ли да зареждате повече информация, моля