In a double pipe counter flow heat exchanger, 10,000 kg/h of an oil, having a specific heat of 2095 J/kg K, is cooled from 800C to 500C by 8000 kg/h of water entering at 250C. Determine the heat exchanger area for an overall heat transfer coefficient of 300 W/m2 K. Take Cp of water as 4180 J/kg K.