An Infineon SKB02N60 insulated gate bipolar transistor (IGBT) is mounted to a 50 mm by 50 mm FR4 PCB that is 1.5 mm thick. The collector is soldered to a 6 cm2 area of 70 μm thick copper on only one layer. The PCB is placed vertically in still air. The device is operated in steady state at an ambient temperature of 50 ºC and it dissipating 1.5 W. What is the maximum junction temperature that you would expect under these conditions in degrees Celsius?