Let $\bf F$ be the radial force field $\mathbf{F} = x\mathbf i + y\mathbf j$. Find the work done by this force along the following two curves, both which go from (0, 0) to (3, 9). (Compare your answers!)

A. If $C_1$ is the parabola: $x = t, \ y = t^2, \ 0 \leq t \leq 3$,
then $\int_{C_1} \mathbf{F} \cdot \, d\mathbf{s} =$

B. If $C_2$ is the parabola: $x = 3 t^2, \ y = 9 t, \ 0 \leq t \leq 1$,
then $\int_{C_2} \mathbf F \cdot \, d\mathbf{s} =$