(1 point) Find the line integral with respect to arc length (72 + 3y)ds. where C is the line segment in the ay-plane with endpoints P = (4, 0) and Q = (0, 8). (a) Find a vector parametric equation r(t) for the line segment C so that points P and Q correspond to t = 0 and t = 1, respectively. T(t) = (b) Using the parametrization in part (a), the line integral with respect to arc length is (72 + 3y)ds = at with limits of integration a = and b (c) Evaluate the line integral with respect to arc length in part (b). (72 + 3y)ds =