Problem $6.$ In a learning curve application, $658\mathrm{.}5$ work hours are required for the third production unit and $615\mathrm{.}7$ work hours are required for the fourth production unit. Determine

$($A$)$ the value of $($n$)$ and

$($B$)$ the value of $($s$)$ which is the slope of the learning curve in Equation $(3-5)$ which is

$Z_u=K(u^n)$