Vectors in Space · Medium problem

A wrench applies a force $\mathbf F = (4, 0, -3)$ newtons at the point with position vector $\mathbf r = (0, 3, 0)$ metres (measured from the pivot at the origin), producing a torque $\boldsymbol\tau = \mathbf r \times \mathbf F$. Find the scalar component of $\boldsymbol\tau$ along the axis direction $(0, 3, 4)$.