Problem 8: The following income statement data presented by Laguna Corporation for the years ended December 31, 2017 and 2018: 2017 2018 Sales P 600,000 P 699,600 Cost of Sales 360,000 380,160 Gross Profit P 240,000 P. 319,440 During 2018, the following transpired that affected net sales, cost of sales, which contributed in the changes in gross margin. 1. Units sold in 2018 was 10% higher than 2017 2. Unit selling price in 2018 was 6% higher than 2017 3. Unit cost in 2018 was 4% lower than 2017 Required: Perform a Gross Margin Analysis under the (a) Two-way; (b) Three-Way; and (c) Four-way method