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(i) 1.5 Vo
(ii) V = IR
1.2 = I x 3 - I = 0.4 A
(iii) E = V + Ir
1.5 = 1.2 + 0.4r
r = $\frac{0.3}{0.4}$ = 0.75 ohms
johnmulu answered the question on May 23, 2017 at 12:36
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