this is the 4 hyperlinks to questions
https://isaacphysics.org/questions/bulbs_and_power?board=electrical_power
https://isaacphysics.org/questions/drift_velocity?board=resistivity
https://isaacphysics.org/questions/finding_the_internal_resistance_sym?board=internal_resistance
https://isaacphysics.org/questions/resistance_and_power?board=internal_resistance
I would really appreciate if you could send working out