Suppose that a firm in a competitive market faces the following revenues and costs: Quantity Total Revenue Total Cost 0 $0 $3 1 $6 $5 2 $12 $8 3 $18 $12 4 $24 $17 5 $30 $23 6 $36 $30 7 $42 $38 Refer to Table 14-8. The firm should not produce an output level beyond Group of answer choices 6 units. 7 units. 5 units. 4 units