A 220V, 20 kW DC shunt motor running at its rated speed of 1200 rpm is to be braked by plugging. Ra=0.1 ohm and rated efficiency is 88% Calculate (i) R to be connected in series with the armature such that braking current is less than or equal to twice full load current.(ii)Initial braking torque. (iii)The torque when motor speed falls to 400 rpm. (1.98 Ω, 318.3 Nm, 214.72 Nm)