Compute each part of given problem:
Problem: A heating element of resistance (at its operating temperature) 209ohms is connected to a battery of emf 120V and unknown internal resistance r. It is found that heat energy is being generated in the internal resistance of the battery.
Part A: What must be the total (combined equivalent) resistance for the current?
Part B: What is the internal resistance?
Part C: At what rate is heat energy being generated in the internal resistance of the battery?
I need help to find at what rate is heat energy being generated in the internal resistance of the battery.