A brick of 203 × 102 × 57 mm in dimension is being burned in a kiln to 1100°C, and then allowed to cool in a room with ambient air temperature of 30°C and convection heat transfer coefficient of 5 W/m²·K. If the brick has properties of ρ = 1920 kg/m³, c_p = 790 J/kg·K, and k = 0.90 W/m·K, determine the time required to cool the brick to a temperature difference of 5°C from the ambient air temperature.