Smart Appliances Ltd. provides the following cost details for its two product categories, Washing Machines and Refrigerators:

Particulars	Washing Machines (₹)	Refrigerators (₹)
Direct Material	2,00,000	2,50,000
Direct Labour	2,40,000	2,80,000
Factory Overheads	2,80,000	3,20,000
Selling and Distribution	1,00,000	1,20,000

Requirements:

1. Calculate the total cost for each product category.
2. Determine the cost per unit if the production volumes are 3,000 units for Washing Machines and 4,000 units for Refrigerators.
3. Compute the selling price per unit if the desired profit margin is 18% on cost.
4. Evaluate the new total cost if factory overheads increase by 12%.