You have been provided with an accumulator E, a standard resistor Rx, two resistance boxes R\(B_1\) and R\(B_2\), two keys \(K_1\) and \(K_2\) and other necessary apparatus. Measure and record the e.m.f of the accumulator. Connect a circuit as shown above. Set the resistance R, in the resistance box such that R in R\(B_1\) = R in R\(B_2\) = 1\(\Omega\). With \(K_1\) open and \(K_2\) closed, measure and record the potential difference V across the standard resistor Rx. (v) Close K, and K,. Read and record the potential difference \(V_o\) across Rx. Evaluate V\(_{1}^{-1}\) Repeat procedure (v) for four other values of R = 2, 3, 4 and 5\(\Omega\) respectively. In each case, ensure that the value of R in R\(B_1\) is equal to the value of R in R\(B_2\). Evaluate V\(_{1}^{-1}\) in each case. Tabulate your readings. Plot a graph of V\(_{1}^{-1}\) on the vertical axis against R on the horizontal axis starting both axes from the origin (0,0). Determine the slope, s, of the graph and the intercept on the vertical axis. Evaluate y = \(\frac{1}{s}\) State two precautions taken to ensure accurate results (b)i. Explain what is meant by the potential difference between two points in an electric circuit ii. A cell has an e.m.f. of 3 V. When it is connected across a resistor of resistance 4\(\Omega\), a current 0.5A passes through the circuit. Calculate the internal resistance of the cell.