A square steel bar of side length w = 0.18 m has a thermal conductivity of k = 14.6 J/(s⋅m⋅°C) and is L = 1.7 m long. Once end is placed near a blowtorch so that the temperature is T1 = 88° C while the other end rests on a block of ice so that the temperature is a constant T2.Input an expression for the heat transferred to the cold end of the bar as a function of time, using A-w2 as the cross-s area of the bar.