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1. Determine the volume of a sphere of radius r. [A sphere is swept out when the region bounded bv the xaxis and the top half of the circle x2 + 3:2 = r2 is revolved about the xaxis.] 2. Calculate the volume swept out when the top half of the elliptical region bounded by i:+ya = 1.wharaa 3: b, cl: 1:3 is revolved around the xaxis (Fig. 41}. Fig. 4| The graphs of the functions in problems 3 is a straight line. Calculate each length {a} using the distance formula between 2 points and {b} by setting up and evaluating the arc length integrals. 3. y=5xfor15x54 AL Calculate the length of y: 4x3f2for1x 59