Consider the circuit in the following diagram, where the resistances are R1 = 0.15R, R2 = 2R, R3 = 0.75R, and R4 = 5R, where R = 33 Ω. The circuit is connected to a V = 3.9 V source.
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Part (a) Input an expression for the equivalent resistance of the circuit in terms of R1, R2, R3, and R4.
Part (b) Input an expression using the Req and V for power expended by the circuit.
Part (c) What is the power P, in watts?