Question

form helium. a star that gets it energy from this hydrogen to helium conversion is a d. main sequence star. when the hydrogen in a star’s core is used up, the helium fuses into heavier elements, like iron, and swell to a much larger size. a star with the same surface temperature, but a much larger radius and luminosity than a main sequence star, is a b. giant star. when the helium from a star’s core is gone and fusion stops, the gases released from a star form a f. planetary nebula. the exposed, dense core of hot carbon and oxygen from a star that no longer supports fusion is a j. white dwarf some stars are so big that they do not become white dwarfs. instead, they collapse quickly resulting in an enormous explosion of energy and light called a select one. the heavy elements in the core can become crushed together to form a neutron star. supernovae from the most massive stars do not become neutron stars. instead, they collapse into an area so dense that nothing can escape its gravity. this is called a select one. nothing in the universe is more extreme, and even light cannot escape one. scientists believe that a black hole exists at the center of virtually every galaxy, including the milky way. the next time you go out to gaze at the stars, consider the power and energy condensed in those pinpricks of light.

Explanation:

1. Massive stars collapse rapidly after fusion stops, releasing enormous energy in an explosion called a supernova.
2. The densest collapse product of massive stars, where gravity traps even light, is a black hole.

Answer:

supernova
black hole