Current Attempt in Progress

The position vector of a particle is given by $r=9ti+1\mathrm{.}8t^{2}j-0\mathrm{.}5(t^3-8)k,$ where $t$ is the time in seconds from the start of the motion and where $r$ is expressed in meters. For the condition when $t=6s,$ determine the power $P$ developed by the force $F=26i-42j-45kN$ which acts on the particle.

Answer: $P=KW$