Relate hydrostatic equilibrium to the star's mass, composition, ...

[Starlight]

Relate hydrostatic equilibrium to the star's mass, composition, and evolution off the main sequence.
 
  What will be an ideal response?

Question 2

The concept of hydrostatic equilibrium is critical to understanding how the Sun has remained stable long enough for life to evolve here.
 
  Indicate whether the statement is true or false

[chevyboi1976]

Answer to Question 1

Hydrostatic equilibrium means that the inward force of gravity, a product of the star's mass, is exactly balanced by the outward radiation pressure of its thermonuclear reactions; as long as the hydrogen supply is abundant, this balance can be maintained, and the star is stable on the main sequence. Once the core helium content grows, and the hydrogen burning shell expands, this extra radiation temporarily overwhelms gravity, and the star begins swelling into its giant stage of evolution.

Answer to Question 2

TRUE