Represent the line segment from P to Q by a vector-valued function. (P corresponds to t-0. corresponds to t = 1.) P(-4,-2, -1), 01-2, -6, -9) (x(t) + y(t) +z(t)) r(t) = Represent the line segment from P to Q by a set of parametric equations. (Enter your answers as a comma-separated list of equations.) x=-2 -21, y = -6 + 41, z=-9+81