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A box slides up an incline, comes to rest, and then slides down again, accelerating in both directions. Answer the following questions, using only a free-body diagram and without doing any calculations: (a) If there is no friction on the incline, how will the box's acceleration going up compare in magnitude and direction with its acceleration going down? (b) If there is kinetic friction on the incline, how will the box's acceleration going up compare in magnitude and direction with its acceleration going down? (c) What will be the box's acceleration at its highest point?
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