A block is launched with an initial speed 2.2 m/s up a frictionless.

A. A block is launched with initial speed 2.2 m/s up a frictionless, inclined ramp. It slides 49 cm up the ramp before heading back down.
What’s the inclination angle of the ramp?
B. Suppose the angles shown in (Figure 1) are 60∘ and20∘.
If the right-hand mass is 6.7 kg, what should be the left-hand mass so that it accelerates upward at 0.64 m/s2?
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C. It takes 510 J of work to push a 60-kg box at constant speed across a 4.8-m-wide room.
What’s the coefficient of friction between box and floor?