need help solving $($b$)$

the table is listed as from top to bottom,net credit sales,uncollectiable accounts,billing and mailing cost, credit investigation fees,collection agency fees,salary of accounts receivable,total credit and collection expenses,total expenses as a percantage of net credit sales. The entire question:Emilio and Ren$$ Santos own Club Cheyenne. From its inception, Club Cheyenne has sold merchandise on either a cash or credit basis, but no credit cards have been accepted. During the past several months, the Santos have begun to question their credit$-$sales policies. First, they have lost some sales because of their refusal to accept credit cards. Second, representatives of two metropolitan banks have convinced them to accept their national credit cards. One bank, Business National Bank, has stated that $(1)$ its credit card fee is $4\%$ and $(2)$ it pays the retailer $96$ cents on each $$1$ of sales within $3$ days of receiving the credit card billings.

The Santos decide that they should determine the cost of carrying their own credit sales. From the accounting records of the past $3$ years, they accumulate these data:

$\backslash$table$[[,2022,2021,2020],[$Net credit sales,$$560,000,$$$610,000,$$$380,000$

Credit and collection expenses as a percentage of net credit sales are as follows: uncollectible accounts $1\mathrm{.}2\%,$ billing

and mailing costs $0\mathrm{.}5\%,$ and credit investigation fee on new customers $0\mathrm{.}2\%.$ Emilio and Ren$$ also determine that the average accounts receivable balance outstanding during the year is $5\%$ of net credit sales. The Santos estimate that they could earn an average of $14\%$ annually on cash invested in other business

opportunities.