A company has a static budget at 10,000 units of production, which shows direct material cost of $80,000, direct labor cost of $60,000, and factory overhead costs of $37,000. Factory overhead costs are 40% fixed. At 6,000 units of production, a flexible budget would include which of the following amounts as total production costs?

a. $112,120

b. $106,200

c. $121,000

d. $115,080