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Question 12 The force F {in pounds] acting at an angle 3 with the horizontal that is needed to drag a crate weighing H" pounds along a horizontal surface at a constant velocity is given by F \"W _ 059 + ysin where p: is a constant called the caecienr ofsdlhg'ictiou between the crate and the surface (see the accompanying gure]. Suppose that the crate weighs 150 lb and that}: = 0.3. (a) Find dF M3 when 3=3. Express the answer in units ofpoundsfdegree. {h} Find (if? id: when 9 =30" if is decreasing at the rate of 0.50/9 at this instant