how did they get the 12960 in this question

The Ballentine Company expects sales for June, July, and August of $48,000, $54,000, and $44,000, respectively. Experience suggests that 40% of sales are for cash and 60% are on credit. The company collects 50% of its credit sales in the month following sale, 45% in the second month following sale, and 5% are not collected. What are the company's expected cash receipts for August from its current and past sales?

Select one:

a. $29,160.

b. $46,760.

c. $61,160.

d. $66,200.

e. $78,800.