$15-5$ RECEIVABLES INVESTMENT McDowell Industries sells on terms of $3/10,$ net $30.$ Total sales for the year are $$912,500$;$40\%$ of the customers pay on the $10$th day and take discounts, while the other $60\%$ pay, on average, $40$ days after their purchases.

a$.$ What is the days' sales outstanding?

b$.$ What is the average amount of receivables?

c$.$ What is the percentage cost of trade credit to customers who take the discount?

d$.$ What is the percentage cost of trade credit to customers who do not take the discount and pay in $40$ days?

e$.$ What would happen to McDowell's accounts receivable if it toughened up on its collection policy with the result that all nondiscount customers paid on the $30$th day?