Question

identify the factor that determines the lifespan of the sun and other stars.

Explanation:

The lifespan of stars, including the Sun, is mainly determined by their mass. More massive stars burn through their nuclear fuel (hydrogen) at a much faster rate in nuclear fusion reactions in their cores. This is because higher mass leads to higher core temperatures and pressures, accelerating the fusion process. For example, a very massive star might live only a few million years, while a low - mass star (like a red dwarf) can live for trillions of years. The Sun, being a medium - mass star, has an estimated lifespan of about 10 billion years.

Answer:

The mass of the star.