An adiabatic heat exchanger is used to heat cold water at 15°C entering at the rate of 10kg/sec by hot air at 90°C entering at the rate of 10 kg/sec. if the exit temperature of cold water IS 29°C then what will be the temperature of hot air at the exit. Cp for air = 1.008 KJ/Kg. Cp for water = 4.18 KJ/Kg:

• A. 26.54°C
• B. 31.88°C
• C. 58.65°C
• D. 89.12°C