1. A 64.0-kg person holding two 0.750-kg bricks stands on a 2.20-kg skateboard. Initially, the skateboard and the person are at rest. The person now throws the two bricks at the same time so that their speed relative to the person is 15.0m/s .
a) What is the recoil speed of the person and the skateboard relative to the ground, assuming the skateboard moves without friction?