A jar contains 'x' liters of Milk, a seller withdraws 25 liter of it and sells it at Rs.20 per liter. He then replaces it water. He repeated the process total three times. Every time while selling he reduces selling price by Rs.2. After this process Milk left in the mixture is only 108 liters so he decided to sell the entire Mixture at Rs. 15 per liter. Then how much profit did he earned if bought Milk at Rs.20 per liter? 1. Rs.50 2. Rs.70 3. Rs.90 4. Rs.100 5. None