Lindsay Corporation had the following account balances:

Sales Revenue $100,000

Beginning Inventory $20,000

Purchases $40,000

Sales Discounts $2,000

Purchase Discounts $1,500

Freight-in $500

Ending inventory $15,000

Purchase returns and allowances $1,000

Given this information and assuming that Lindsay's total operating expenses (exclusive of cost of goods sold) are $20,000, pretax income is?

a) $57,000

b) $55,000

c) $23,000

d) $35,000