What is the difference between reflection and refraction

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?

The roller coaster from problem #1 then tops a second hill at 15.0 m/s, how high is the second hill? 91.5 m 79.2 m 80.0 m 68.5 m

Part a determine the magnitude of the x component of f using scalar notation. fx f x = nothing lb request answer part b determine the magnitude of the y component of f using scalar notation. fy f y = nothing lb request answer part c determine the magnitude of the z component of f using scalar notation. fz f z = nothing lb request answer provide feedback figure1 of 1a force vector acting on a ring attached to the ground is shown in the xyz space together with its x, y, and z components lying on the corresponding positive axes. the ring is located at the origin. force f is located in the first octant. f makes an angle of 60 degrees with its x component and an angle of 45 degrees with its y component. a force vector acting on a ring attached to the ground is shown in the xyz space together with its x, y, and z components lying on the corresponding positive axes. the ring is located at the origin. force f is located in the first octant. f makes an angle of 60 degrees with its x component and an angle of 45 degrees with its y component.