Rainbow Ltd sells goods to customers on cash and credit terms. If customers purchase goods on credit, they are allowed exactly one month to pay. Rainbow Ltd budgeted for sales of $15,000 in July with 20% being cash sales; sales of $12,000 in August, 75% of this amount in cash; and sales of $8,000, all on credit, in September. How much total cash will Rainbow budget to receive in August?

Select one: a. $15,000

b. $21,000

c. $3,000

d. $12,000