An all$-$day study at a manufacturing company revealed the following noise sources: $0\mathrm{.}5$ hrs$.,100$ dBA; $1$ hr$.,$ less than $80$ dBA; $3\mathrm{.}5$ hrs$.,90$ dBA; $3$ hrs$.,92$ dBA. Consider that the last exposure is in a press room which currently has five presses operating. Assuming the company can eliminate some of the presses and transfer production to the remaining presses,