An overhead continuous conveyor is used to carry dishwasher base parts along a manual assembly line while components are being added to them. Spacing between base parts $=2\mathrm{.}4$ m and the speed of the conveyor $=1\mathrm{.}2$ m$/$min$.$ The length of each workstation is $3\mathrm{.}2$ m$.$ There are a total of $25$ stations, four of which have two workers. Three utility workers are also assigned to the line. Determine $($a$)$ tolerance time, $($b$)$ manning level, and $($c$)$ elapsed time a dishwasher base part spends on the line.