The following information is given about M/s. Tiara Ltd.: Number of Units manufactured during the month - 1,000, Direct materials consumed - 20,000, Direct labour - 8,000, Indirect labour (in factory)- 2,500, Supervision costs (in factory)- 1,000, Factory premises rent - 1,600, Factory lighting - 600, Oil for machines - 100, Depreciation of machines - 500, Office overheads - 8,000. Office salaries - 2,000, Misc. office expenses - 1,000, Selling and distribution overheads - 6,000. A profit margin of 20% on the total cost of goods is expected on the sale of the units. 

What is the prime cost?