Physics Work,Power & Energy Level: Misc Level

Bobby accelerates from rest at 121 m/s2 for 1.2 seconds. He then runs along level ground at that speed until he jumps onto a stationary wagon fully loaded with large cement blocks. The wagon and the blocks have a total mass of 122 kg.(No friction involved in this problem. It,s a frictionless environment,) As the wagon, with Bobby on board, rolls along it encounters a hill inclined upward at 15 degrees. The wagon then rolls up the hill a distance of 11.3 m ( along the ground) before coming to a stop.Determine Bobby,s mass.