ABC Corporation sold merchandise worth $10,000 to a customer on credit terms of 2/10, n/30. The cost of the merchandise sold was $6,000. The customer returned $2,000 worth of defective merchandise, and ABC Corporation issued a credit note for the return. The customer paid the remaining balance within the discount period. Calculate the following:

a) The amount of the cash discount available to the customer if they pay within the discount period.

b) The net amount receivable by ABC Corporation if the customer takes advantage of the discount.

c) The net amount receivable by ABC Corporation if the customer pays within the credit period without taking the discount.

d) The net amount receivable by ABC Corporation if the customer fails to pay within the credit period and incurs a late payment penalty of 2%.