model for the problem is as follows:

Max $63E+95S+135D$

$s.t.$

$1E+1S+1D260$ Fan motors

$1E+2S+4D340$ Cooling coils

$8E+12S+14D2,600$ Manufacturing time

The computer solution is shown below.

$($a$)$ Identify the range of optimality for each objective function coefficient. $($If there is no upper or lower limit$,$ enter NO LIMIT.$)$

$($c$)$ Identify the range of feasibility for the right$-$hand$-$side values. $($If there is no upper or lower limit$,$ enter NO LIMIT.$)$

constraint $1$

to

constraint $2$

to