please answer all 15,16, and 17 with explanations/work

Questions 15-17 all refer to the following scenario. A 35 kg child ziplines from rest on a platform 12 m high to the ground with negligible friction. In the last 8 m of the zipline, which is approximately horizontal, a braking mechanism applies a constant force opposing the motion to slow the child down so that she's travelling at 2.5 m/s when she finally lands on the safety padding at the end. The padding compresses for 1.5 s when the child lands on it and stops. 15. What is the magnitude of the force applied by the braking mechanism? E 350 N (B) 511 N (C) 525 N 4090 N 16. What is the average force acting on the child as she comes to a stop on the safety padding? (A) 1.7 N (B) 58 N (C) 73 N D 150 N 17. If the height of the platform had been 15 m, by what fac- tor would her maximum speed have increased? (A) 2 (B) (C) (D) N / U