001 (part 1 of 2) 10.0 points

An 86 kg fullback moving east with a speed
of 5.5 m/s is tackled by a 97 kg opponent
running west at 3.6 m/s, and the collision is
perfectly inelastic.
a) What is the velocity of the players immediately after the tackle?
Answer in units of m/s.
002 (part 2 of 2) 10.0 points
b) What is the decrease in kinetic energy
during the collision?
Answer in units of J.