In the final stages of production, a pharmaceutical is sterilized by heating it from 25 to 75°C as it moves at 0.21 m/s through a straight thin-walled stainless steel tube of 12.7-mm diameter. A uniform heat flux is maintained by an electric resistance heater wrapped around the outer surface of the tube. If the tube is 10 m long, what is the required heat flux? If fluid enters the tube with a fully developed velocity profile and a uniform temperature profile, what is the surface temperature at the tube exit? Fluid properties may be approximated as 1000 kg/m3, 4000 J/kg·K, 2 × 10-3 kg/s·m, 0.8 W/m·K, and 10.