A worker performs a repetitive assembly task at aworkbench to assemble products. Each product consistsof $25$ components. Various hand tools are used in thetask. The standard time for the work cycle is $7\mathrm{.}45$ min,based on using a PFD allowance factor of $15\%.$ If theworker completes $75$ product units during an $8-$hourshift, determine $($a$)$ the number of standard hoursaccomplished and $($b$)$ worker efficiency. $($c$)$ If the workertook only one rest break, lasting $13$ min, andexperienced no other interruptions during the $8$ hours ofshift time, determine her worker performance.