Answer:
1. Hydrogen decrease and helium increase
2. Equilibrium
3. Upper Left
4. for about 90% of their lifetimes
5. Moons
Explanation:
1. As the Sun will get older the Hydrogen in the core will decrease and amount of Helium will increase. There will be a time when hydrogen will finish up in the Sun and fusion of helium will start thus making new elements.
2. The shape of the Sun is maintained when there is an equilibrium between the outward thermal pressure and inward gravitational pull.
3. Such stars will be placed on the upper left of the HR diagram which is a plot showing the relation of stars absolute magnitude and luminosity versus their temperature and spectral class.
4. A star spends around 90% of its lifetime as a main sequence star.
5. Only Mercury and Venus do not have moons out of all the planets in the Solar system. Rest all the 6 planets have at least one moon with Jupiter having 79 of them.
