Quality Air Conditioning manufactures three home air conditioners: an economy model, a standard model, and a deluxe model. The profits per unit are $63, $95, and $135, respectively. The production requirements per unit are as follows:

	Number of Fans	Number of Cooling Coils	Manufacturing Time (hours)
Economy	1	1	8
Standard	1	2	12
Deluxe	1	4	14

For the coming production period, the company has 200 fan motors, 320 cooling coils, and 2400 hours of manufacturing time available. How many economy models (E), standard models (S), and deluxe models (D) should the company produce in order to maximize profit? The linear programming model for the problem is as follows:

Max	63E	+	95S	+	135D
s.t.
	1E	+	1S	+	1D		200	Fan motors
	1E	+	2S	+	4D		320	Cooling coils
	8E	+	12S	+	14D		2400	Manufacturing time
E, S, D 0

The computer solution is shown in the figure below.

Optimal Objective Value = 16440.00000
		Variable		Value		Reduced Cost
		E		80.00000		0.00000
		S		120.00000		0.00000
		D		0.00000		-24.00000
		Constraint		Slack/Surplus		Dual Value
		Fan motors		0.00000		31.00000
		Cooling coils		0.00000		32.00000
		Manufacturing time		320.00000		0.00000

		Variable		Objective Coefficient		Allowable Increase		Allowable Decrease
		E		63.00000		12.00000		15.50000
		S		95.00000		31.00000		8.00000
		D		135.00000		24.00000		Infinite
		Constraint		RHS Value		Allowable Increase		Allowable Decrease
		Fan motors		200.00000		80.00000		40.00000
		Cooling coils		320.00000		80.00000		120.00000
		Manufacturing time		2400.00000		Infinite		320.00000

Which constraint shows extra capacity? How much?

What is the optimal solution for standard models (S)?