A child is enjoying a swing at the park. At the bottom of the swing, they have a kinetic energy of 6028 J and a velocity of 20 m/s. What is the mass of the child? ​

22. the top of a cliff is located a distance h above the ground. at a distance h/2 there is a branch that juts out from the side of the cliff, and on this branch a bird's nest is located. two children throw stones at the nest with the same initial speed, one stone straight downward from the top of the cliff and the other stone straight upward from the ground. in the absence of air resistance, which stone hits the nest in the least amount of time?