Border Corporation is a service company that measures its output by the number of customers served. The company has provided the following fixed and variable cost estimates that it uses for budgeting purposes. Fixed Element per Month Variable Element per Customer Served Revenue $ 4,200 Employee salaries and wages $ 41,300 $ 1,200 Travel expenses $ 500 Other expenses $ 33,000 When the company prepared its planning budget at the beginning of July, it assumed that 33 customers would have been served. The amount shown for net operating income in the planning budget for July would have been: a. ($4,300). b. ($1,414). c. ($1,200). d. $8,200.