^{On August 12, a company provided goods to a customer for 3000 with terms 2/10, n/30. On August 16, the customer returned $600 of goods. On August 18,the customer was not completely satisfied with the customer service and so the company granted an allowance $400 on the amount owned. Finally, on August 20, the customer made full payment and the balance owed, excluding the allowance, returns, and the discount.}

Do the journal entries for:

1) The original sale on August 12.

2) The sales return on August 16.

3) The sales allowance on August 18.

4) The cash collection by the company from the customer and the sale discount.