I need details calculation on how to get the pressure at point x. ​

The “death throes” of stars are amongst the most complex phenomena in all of astronomy, and the “corpses” of stars amongst the most energetic and exotic objects in existence. beginning at the end of the core helium fusion stage in a star’s life, describe in detail the post-main sequence development of both (a) a 1.0 solar mass star, and (b) a 25.0 solar mass star. in what significant ways do they differ? what role does each of these types of stars play in the "star-gas-star" cycle and the evolution of chemical elements in our galaxy?

An object weighs 40n in air, weighs 20n when submerged in water and 30n when submerged in a liquid of unknown density. what is the density of the liquid?

It is really hard for me right know