A double-pipe parallel-flow heat exchanger is used to heat water (cp=4180J/kgK) from 25C to 60C at a rate of 0.2kg/s. The heating is accomplished by geothermal water (cp=4310J/kgK) available at 123C at a mass flow rate of 0.3kg/s. The inner tube is thin-walled and has a diameter of 0.8cm. If the overall heat transfer coefficient of the heat exchanger is 550W/m2K, determine the length of the tube required to achieve the desired heating. (Round the answer to a single decimal place.) The length of the tube required to achieve the desired heating is m