When a car's starter is in use, it draws a large current. The car's lights draw much less current. As a certain car is starting, the current through the battery is 61.2 A and the potential difference across the battery terminals is 8.64 V. when only the car's lights are used, the current through the battery is 1.98 A and the terminal potential difference is 10.7 V. Find the battery's emf. [:1 Find the internal resistance. :1