Dad is pushing his son on the merry-go-round in the park. The merry-go-round has a mass of 160 kg and a diameter of 2.40 m. His 35 kg son is sitting 0.8 m from the center. If dad pushes with a tangential force of 32 N for 1.3 seconds three times, how fast is his son moving tangentially if the merry-go-round starts from rest?