Salvadore Inc., a local retailer, has provided the following data for the month of September:

Merchandise inventory, beginning balance $ 46,800
Merchandise inventory, ending balance $ 45,000
Sales $265,200
Purchases of merchandise inventory $133,100
Selling expense $ 24,900
Administrative expense $ 54,700

The net operating income for September was:
$50,700
$46,900
$133,100
$132,100