Use the following information to answer this question.

Windswept, Inc. 2017 Income Statement ($ in millions)
Net sales	$	9,710
Cost of goods sold		7,990
Depreciation		475
Earnings before interest and taxes	$	1,245
Interest paid		114
Taxable income	$	1,131
Taxes		396
Net income	$	735

Windswept, Inc. 2016 and 2017 Balance Sheets ($ in millions)
		2016			2017				2016			2017
Cash	$	270		$	300		Accounts payable	$	1,550		$	1,785
Accounts rec.		1,080			980		Long-term debt		1,160			1,330
Inventory		1,940			1,745		Common stock		3,460			3,060
Total	$	3,290		$	3,025		Retained earnings		650			900
Net fixed assets		3,530			4,050
Total assets	$	6,820		$	7,075		Total liab. & equity	$	6,820		$	7,075

What is the days' sales in receivables for 2017?

36.33 days

36.84 days

81.54 days

38.72 days

50.56 days