I need help setting up this word problem, i know i need to use limits

The distance an airplane has flown atthours is given by

S(t) = 600t + $\displaystyle 30t^2 - 4t^3$, where S is the distance in kilometers and 0 $\displaystyle x\leq t\leq 5$. Estimate the instantaneous rate of change in distance at exactly 2 h.