54 The gure shows a circuit diagram. If R] = 14709, R2 = 2.02.63 9, R3 = "15309, R4 = 52052, V1 = 30.6 V, V2 = 21.8 V, and V3 = 25.5 V, determine (a) the current, (b) the electric potential of wire A relative to ground, and (c) the voltage drop across R3. Hint: Use Kirchhoff's loop rule in part (a). \" v 2 (a) Current. mA ( i 0.02 mA) (b) Electric potential V( i 0.2 V) (c) Voltage drop. V( i 0.02 V)