The financial statements of DEF Inc. for the year ending 30-06-2020 show the following:

	$
Cash	1,80,000
Sundry debtors	7,00,000
Short term investment	5,50,000
Stock	24,00,000
Prepaid expenses	30,000

Total current assets: $38,60,000

	$
Current liabilities	10,50,000
8% Debentures	15,00,000
Equity share capital	20,00,000
Retained earnings	14,00,000

Statement of Profit for the year ending 30-06-2020

	$
Sales (40% cash sales)	55,00,000
Less: Cost of goods sold	37,00,000
Profit before interest & tax	18,00,000
Less: Interest	2,00,000
Profit before tax	16,00,000
Less: Tax @20%	3,20,000

Net Profit: $12,80,000

Calculate: (i) Working capital ratio, (ii) Debt service coverage ratio, (iii) Gross profit margin, and (iv) Operating cycle.