An optimization specialist studied a factory's existing processes and work-flow to implemented new equipment and updated production processes. After the new equipment and processes were in place, he studied the production and modeled the productivity with the following function: P(t) = - 5t + 82.5t + 5t, where t is the number of hours worked in a 10-hour shift. Find the point of diminishing returns for this factory. The point of diminishing returns is at t = Submit