Fig.shows a potentiometer with a cell of 2.0 V and internal resistance 0.40 Omegamaintaining a potential drop across the resistor wire AB. A standard cell which maintains a constant emf of 1.02 V (for very moderate currents up to a few mA) gives a balance point at 67.3 cm length of the wire. To ensure very low currents drawn from the standard cell, a very high resistance of 600 kOmegais put in series with it, which is shorted close to the balance point. The standard cell is then replaced by a cell of unknown emfand the balance point found similarly, turns out to be at 82.3 cm length of the wire.(a) What is the value of epsi ? (b) What purpose does the high resistance of 600 kOmegahave ? (c) Is the balance point affected by this high resistance ? (d) Would the method work in the above situation if the driver cell of the potentiometer had anemf of 1.0 V instead of 2.0 V? (e) Would the circuit work well for determining an extremely small emf, say of the order of afew mV (such as the typical emf of a thermo-couple) ? If not, how will you modify the circuit ?