al derivatives $\vec r_u$, $\vec r_v$ and
      the total derivative $D\vec r(u,v)$, a 3-row by 2-column
      matrix].</li>

      <li>The vector field $\vec F(x,y) = (-y,xe^{3y})$. [Hint:
      compute partial derivatives $\vec F_x$ and $\vec F_y$ and the
      total derivative $D\vec F(x,y)$, a 2-row by 2-column
      matrix.]</li>

      <li>The parametric surface $\vec f(u,v)=(u^2,v^2,u-v)$.</li>

      <li>The space transformation $\vec
      T(r,\theta,z)=(r\cos\theta, r\sin\theta, z)$.</li>
    </ol