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13) (8p) Melissa is skiing downhill, when she passes marker A at which point her speed is measured as 10.50 m/s. She comes down a steep hill, passes over a small hump, and passes Marker B (as shown in the figure), which lies 12.00 m below the level of marker A. Melissa has a mass of 52.0 kg (including her gear). Assume friction did -2550.0 J of work on her, what is her speed passing marker B? (Note: You do not have a constant friction force in this example. Apply the concept that the work by friction changes the mechanical energy.) Marker A 12.0 m 18.0 m Marker B