Computer Products Produces Two Keyboards,Regular and Special B)Maximize $\quad \$ 128 R + \$ 720 S$

Computer Products produces two keyboards,Regular and Special.Regular keyboards have a unit contribution margin of $128,and Special keyboards have a unit contribution margin of $720.The demand for Regulars exceeds Computer Product's production capacity,which is limited by available machine-hours and direct manufacturing labor-hours.The maximum demand for Special keyboards is 80 per month.Management desires a product mix that will maximize the contribution toward fixed costs and profits. Direct manufacturing labor is limited to 1,600 hours a month and machine-hours are limited to 1,200 a month.The Regular keyboards require 20 hours of labor and 8 machine-hours.Special keyboards require 34 labor-hours and 20 machine-hours.
Let R represent Regular keyboards and S represent Special keyboards.The correct set of equations for the keyboard production process is ________.

A) $\begin{array}{ll}\text { Maxindze: }&\$ 128 \mathrm{R}+5720 \mathrm{~S}\\\text { Conslrainls: }\\\text { Labor-hours: } & 20 R+31 S \leq 1,600 \\\text { Machane-hours: } & 8 R+20 S \leq 1,200 \\\text { Special: } & S \leq 80 \\& S \geq 0 \\\text { Regular: } & R \geq 0\end{array}$
B) Maximize: $\quad \$ 128 R + \$ 720 S$
Constraints:
Labor-hours: $\quad 20 \mathrm { R } + 34 \mathrm {~S} \geq 1,600$
Machine-hours: $\quad 8 R + 20 S \geq 1,200$
Special: $\quad S \geq 80$
$\quad\quad\quad\quad S \geq 0$
Regular: $\quad \mathrm { R } \geq 0$
C) $\begin{array}{ll}\text { Maximize: } & \$ 720 \mathrm{~S}+\$ 128 \mathrm{R} \\\text { Constraints: } & \\\text { Labor-hours: } & 20 \mathrm{R}+8 \mathrm{~S} \leq 1,600 \\\text { Machine-hours: } & 34 \mathrm{R}+20 \mathrm{~S} \leq 1,200 \\\text { Special: } & \mathrm{S} \leq 80 \\& \mathrm{~S} \geq 0 \\\text { Regular: } & \mathrm{R} \geq 0\end{array}$
D) $\begin{array}{ll}\text { Maximize: } & \$ 128 \mathrm{R}+\$ 720 \mathrm{~S} \\\text { Constraints: } & \\\text { Labor-hours: } & 20 \mathrm{R}+34 \mathrm{~S} \leq 1,600 \\\text { Machine-hours: } & 8 \mathrm{R}+20 \mathrm{~S} \leq 1,200 \\\text { Special: } & \mathrm{S} \geq 80 \\& \mathrm{~S} \leq 0 \\\text { Regular: } & \mathrm{R} \leq 0\end{array}$