D E G

Direct materials $33.40 $49.90 $56.30

Direct labor 20.80 23.40 14.20

Variable manufacturing overhead 1.80 1.20 0.30

Fixed manufacturing overhead 12.90 8.50 9.10

Unit product cost $68.90 $83.00 $79.90

D E G

Mixing minutes per unit 1.80 0.60 0.10

Selling price per unit $64.00 $86.40 $79.90

Variable selling cost per unit $1.20 $1.70 $1.70

Monthly demand in units 2,600 3,900 1,900

The mixing machines are potentially the constraint in the production facility. A total of 7,110 minutes are available per month on these machines.

Direct labor is a variable cost in this company.

Up to how much should the company be willing to pay for one additional hour of mixing machine time if the company has made the best use of the existing mixing machine capacity?