Two ice skaters of masses 60 kg and 80 kg are initially at rest. They push off each other and glide in opposite directions. Calculate their final velocities if there is no external force acting on them.
a. 0.60 m/s, 0.80 m/s
b. 0.80 m/s, 0.60 m/s
c. 1.20 m/s, 0.90 m/s
d. 0.90 m/s, 1.20 m/s