12. When electricity Flows through a certain kind of light bulb, the voltage applied to the bulb, in volts, and the current owing through it, in amperes, are as shown in the graph. The instantaneous rate of change of voltage with respect to current is known as the resistance of the light bulb. a) Does the resistance increase or decrease as the voltage is increased? Justify your answer. b) Use the graph to determine the resistance of the light bulb at a voltage of 60 V