We are given the power of the iron, 2600W and we know that Power = Energy/Time. We are also given the specific heat capacity of steel (C) which gives us a clue that we should use Q = mcT(delta) (meaning, Energy = massspecific heat capacitychange in temp).Therefore, to see what the heat energy transferred is, we do Q = 0.89kg * 450 * (215-18) = 78898.5 JThen, to see the time taken for this heat energy to be transferred, we do T = E/P = 78898.5 / 2600 = 30.3sTherefore, the plate reaches its working temperature in 30.3s, which is less than 1 minute.