The position vector of a particle is given by $\mathbf{r}=$ $8 t \mathbf{i}+1.2 t^{2} \mathbf{j}-0.5\left(t^{3}-1\right) \mathbf{k},$ where $t$ is the time in seconds from the start of the motion and where $\mathbf{r}$ is expressed in meters. For the condition when $t=$ 4 s, determine the power $P$ developed by the force $\mathbf{F}=40 \mathbf{i}-20 \mathbf{j}-36 \mathbf{k} \mathrm{N}$ which acts on the particle.