dP 1 : (P 1000) At the start of the workday, 35,000 cubic feet of dirt was piled up at a construction site. Dirt will be added to the pile for the next 8 hours, satisfying the increasing differential equation d? 5 where the function P represents the total amount of dirt in the pile. P is measured in cubic feet, and t is measured in hours from the start of the workday. Part A: Estimate the amount of dirt in the pile after 3 hours, using the tangent line to the graph of P at t = 0, (10 points)