What is the first event that happens to a star with roughly the mass of our sun that exhausts the hydrogen in its core and stops the generation of energy by the nuclear fusion of hydrogen to helium? describe the sequence of events that the star undergoes.

Aplayground merry-go-round has a radius of 4.6 m and a moment of inertia of 200 kg-m2 and turns with negligible friction about a vertical axle through its center. a child applies a 26.0 n force tangentially to the edge of the merry-go-round for 15.0 seconds. if the merry-go-round is initially at rest, how much work did the child do on the merry-go-round?