Avon Products, Inc., located in New York City, is one of the world’s largest producers of beauty and related products. The company's consolidated balance sheets for the 2016 and 2015 fiscal years included the following:

2015 2014
Current assets:
Receivables, less allowances of $86,700 in 2015 and $106,900 in 2014: $443,000 $515,600

A disclosure note accompanying the financial statements reported the following ($ in thousands):

Year Ended
2015 2014
Calculation of account receivables, net
Receivables $529,700 $622,500
Less: Allowance for doubtful accounts (77,600) (93,700)
Less: Reserve for product returns (9,100) (13,200)
Trade accounts receivable, net: $443,000 $515,600

Assume that the company reported bad debt expense in 2015 of $144,100 and had products returned for credit totaling $6,800 (sales price). Net sales for 2015 were $6,076,500 ($ in thousands).

Required:

a. What is the amount of accounts receivable due from customers at the end of 2015 and 2014?
b. What amount of accounts receivable did Avon write off during 2015?
c. What is the amount of Avon's gross sales for the 2015 fiscal year?
d. Assuming that all sales are made on a credit basis, what is the amount of cash Avon collected from customers during the 2015 fiscal year?