SK corporation presented the following comparative income statements for 2017 and 2016:

	2017	2016
Net sales	$794,575	$647,483
Other income	11,167	10,411
	805,742	657,894
Costs and expenses:
Material and manufacturing costs of products sold	325,695	233,125
Research and development	67,657	56,550
General and selling	263,340	223,055
Interest	9,384	5,761
Other	7,785	3,653
	673,861	522,144
Earnings before income taxes and minority equity	131,881	135,750
Provision for income taxes	57,251	60,870
Earnings before minority equity	74,630	74,880
Minority equity in earnings	5,528	6,325
Net earnings	$ 69,102	$ 68,555

Other relevant financial information follows:

	2017	2016
Average common shares issued	14,790	14,740
Total long-term debt	$104,564	$106,351
Total stockholders equity (all common)	405,146	360,265
Total assets	718,818	591,055
Operating assets	705,843	579,833
Dividends per share	1.5	1.6
Stock price (December 31)	520/2	750/4

Required:

a. Calculate the following for 2017 and 2016:

Net profit margin (3 marks)

2. Return on assets (using ending assets) (3 marks)

3. Total asset turnover (using ending assets) (3 marks)

4. Operating income margin (3 marks)

5. Operating asset turnover (using ending assets) (3 marks)

6. Return on investment (using ending liabilities and equity) (3 marks)

b. Based on the previous computations, evaluate the trend in profitability for this firm. (2 marks)