An artifact is found in a desert cave. the anthropologists who found this artifact would like to know its age. they find that the present activity of the artifact is 9.25 decays/s and that the mass of carbon in the artifact is 0.100 kg. to find the age of the artifact, they will need to use the following constants: 1. r = 1.2 x 10^{-12},
2. m_a = 2.32 x 10^{-26} kg,
3. lambda = 1.21 x 10^{-4} year^{-1}.
what is the age of the artifact? be mindful of the units.

Abasketball star covers 2.65 m horizontally in a jump to dunk the ball. his motion through space can be modeled precisely as that of a particle at his center of mass. his center of mass is at elevation 1.02 m when he leaves the floor. it reaches a maximum height of 1.90 m above the floor and is at elevation 0.910 m when he touches down again. (a) determine his time of flight (his "hang time"). (b) determine his horizontal velocity at the instant of takeoff. (c) determine his vertical velocity at the instant of takeoff. (d) determine his takeoff angle. (e) for comparison, determine the hang time of a whitetail deer making a jump with center-of-mass elevations yi = 1.20 m, ymax = 2.45 m, and yf = 0.750 m.