A slab of aluminum (2024-T6), which measures 16 cm × 16 cm × 1.5 cm is initially at 750 K. The slab is thenannealed by a water spray at 15°C, which strikes both sides of the slab. The convective heat transfercoefficient is estimated to be 1500 W/m2·K. How much time is required to cool the slab to 320 K? Neglect convection off the edges of the slab since almost all the surface area is on the two 16 cm x 16 cm sides.