Linear programming

In a linear programming problem to determine the contribution-maximising production and sales volumes
for two products, X and Y, the following information is available.
Product X Product Y Total available
per unit per unit per period
Direct labour hours 2 hours 4 hours 10,000 hours
Material X 4 kg 2 kg 14,000 kg
Contribution per unit $12 $18
The profit-maximising level of output and sales is 3,000 units of Product X and 1,000 units of Product Y.
What is the shadow price of a direct labour hour?
A $1.00
B $2.40
C $4.00
D $4.50

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