The more oxygen the muscles receive, the more energy you have

Abearing is designed to a reduce friction b. support a load c.guide moving parts such as wheels, shafts and pivots d. all of the above

15. one purpose of the tread pattern on a tire is to a reduce tire wear. b. reduce traction c. allow water to flow away from the tire. d. look impressive.

When the displacement of a mass on a spring is 12a the half of the amplitude, what fraction of the mechanical energy is kinetic energy? at what displacement, as a fraction of a, is the mechanical energy half kinetic and half potential?