18. Spencer Company expects cash sales for July of $12,000, and a 10% monthly increase during each of August and of September. Credit sales of $4,000 in July should be followed by 25% increases during during each of August and of September. Budgeted cash sales and budgeted credit sales for September are, respectively: a. $14,520 and $6,250 b. $13,200 and $6,000 c. $14,520 and $6,000 d. $14,400 and $6,250