A typical car battery can be modeled as an ideal source E connected in series with an internal resistance Rbatt. Assume you have a good battery for which Egood = 12.0 V and Rbatt, good = 0.0200 Ω and a dead one for which Edead = 10.8 V and Rbatt, dead = 0.300 Ω .

Calculate the current through the batteries connected in series.
Calculate the current through the batteries connected in parallel.