Athin electrical heating element provides a uniform heat flux qo" to the outer surface of a duct through which air flows. the duct wall has a thickness of 10 mm and a thermal conductivity of 20 w/m·k. (a) at a particular location, the air temperature is 30°c and the convection heat transfer coefficient between the air and inner surface of the duct is 100 w/m2·k. what heat flux is required to maintain the inner surface of the duct at ti = 58°c? (b) for the conditions of part (a), what is the temperature to of the duct surface next to the heater?