The circuit shown in the figure below contains two batteries, each with an emf and an internal resistance, and two resistors. (R1 = 3.5 Ω, R2 = 9.0 Ω, R3 = 1.7 Ω, V = 16.0 V.)
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(a) Find the current in the circuit (magnitude and direction).
(b) Find the terminal voltage Vab of the 16.0 V battery.
(c) Find the potential difference Vac of point a with respect to point c.