Walsh Corporation's relevant range of activity is 7,000 units to 11,000 units. When it produces and sells 9,000 units, its average costs per unit are as follows: Average Cost per Unit Direct materials Direct labor 4.85 4.20 Variable manufacturing overhead $ 1.55 Fixed manufacturing overhead $ 9.00 Fixed selling expense $ 3.15 Fixed administrative expense $ 1.80 Sales commissions $ 0.50 Variable administrative expense $ 0.45 The incremental manufacturing cost that the company will incur if it increases production from 9,000 to 9,001 units is closest to: Select one: O a $10.60 O b. $19.60 Oc. $22.75 Od. $25.50