Two ice skaters, one with mass of 45kg and the other was a mass of 60kg, are moving together at 0.20m/s with the 60kg skater in front. After they have pushed off from one another, the speed of the 60kg skater is 0.257 m/s in the same direction as the original combined-skater velocity. What is the speed of the 75kg skater after they have pushed off?