Fluid flows through a pipe with a velocity of \(2.0 \mathrm{ft} / \mathrm{s}\) and is being heated, so the fluid temperature \(T\) at axial position \(x\) increases at a steady rate of \(30.0^{\circ} \mathrm{F} / \mathrm{min}\). In addition, the fluid temperature is increasing in the axial direction at the rate of \(2.0^{\circ} \mathrm{F} / \mathrm{ft}\). Find the value of the material derivative \(D T / D t\) at position \(x\).