Lightbulbs act as resistors. Janine is building a circuit that contains two lightbulbs in parallel. One of the lightbulbs has a resistance of 120 ohms, but the resistance of the second lightbulb is unknown. She models the total resistance in the circuit, t, with this equation, in which r represents the resistance of the second lightbulb. t=120r/r+120 <- (Janine's equation)

Find the inverse of Janine's equation.

Janine determines that the total resistance in her circuit is 80 ohms. Using the inverse equation modeling this situation, find the resistance of the second lightbulb.

A.300
B.120
C.240
D.40