Evaluate the Following Derivative $\frac { \mathrm { d } } { \mathrm { d } t } \left( a t ^ { 2 } + q t + r \right)$

Evaluate the following derivative.
​ $\frac { \mathrm { d } } { \mathrm { d } t } \left( a t ^ { 2 } + q t + r \right)$