If $f(x) = \left(x^{3}+6\right)^{2}$ then $\frac{df}{dx} =$
The slope of the tangent line to $f$ at $x = -6$ is
If $s(t) = \left(t^{3}+6\right)^{2}$ is the displacement of a car from home (in meters) at time t (in hours) find the velocity of the car at time $t = 9$ with units: