Two resistances A and B of 10 Ω and 20 Ω respectively are connected in parallel with a 6 V battery. The total energy supplied to the circuit by the battery in 1 second will be ______.

A wire of a given material has length l and cross-sectional area A, and its resistance is 9 Ω. Another wire of the same material has length l/3 and cross-sectional area 3A. What will be the resistance of the second wire?

A 7 V battery is connected in series with five resistors: 0.1 Ω, 0.4 Ω, 0.5 Ω, 0.6 Ω, and 12.4 Ω. What is the current flowing through the 12.4 Ω resistor?