the armature of a 230 V shunt motor has a resistance of 0.18 ohms if the armature current is not to exit 76 a calculate (a) the resistance that must be inserted in series with the armature at the instant of starting​ (b) the value to Wich to the resistance can be reduced when the armature accelerate until Ec is 168 volt (c) the armature current at the instant of starting if no resistance is inserted in the armature circuit. (assume a 2 volt at the brushes)