Let a force F be acting on a body free to rotate about a point 0 and let \mathbf{r} the position vector of any point P on the line of action of the force. The torque ($\tau$) of this force about point O is defined as

$\tau =\mathbf{r}\times \mathbf{F}$

Given, $\mathbf{F}=(2\hat{\mathbf{i}}+3\hat{\mathbf{j}}-\hat{\mathbf{k}})$ N and $\mathbf{r}=(\hat{\mathbf{i}}-\hat{\mathbf{j}}+6\hat{\mathbf{k}})$ m

Find the torque of this force.