Peas are being frozen in an air-blast freezer. The initial product temperature is 10C and the cold air -40C. The pea has a 7-cm diameter with density of 1000 kg/m3 , the initial freezing temperature is -1.25C, the thermal conductivity of the frozen pea is 1.2 W/(m K), and the latent heat of fusion is 250 kJ/kg. The convective heat transfer coefficient is 50 W/(m2 K). Calculate the freezing time