Why doesn't the skater ever regain his potential energy?

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?

Acar drives toward the right over the top of a hill, as shown below. which arrow represents the centripetal acceleration? w x y z

Explain what it means to view something from a frame of reference. provide an example that illustrates your explanation. (4 points)