An asbestos pad is square in cross section, measuring 5 cm on a side at its small end, increasing linearly to 10 cm on a side at the large end. The pad is 15 cm high. If the small end is held at 600 K and the large end at 300 K, what heat‐flow rate will be obtained if the four sides are insulated? Assume one‐dimensional heat conduction. The thermal conductivity of asbestos may be taken as 0.173 W/m⋅K.