****Show all forces, motion/free-body diagrams, calculations, equations, significant figures and work. ****

In the gure battery 1 has emf "1 = 23.0 V and internal resistance r1 = 0.017 0 and battery 2 has emf $2 = 23.0 V and internal resistance r2 = 0.012 O. The batteries are connected in series with an external resistance R. (a) What R value makes the terminal-to- terminal potential difference of one of the batteries zero? (b) Which battery is that