Two spherical bodies A and B of diameter d=0.0344mm are heated to the same temperature and allowed to coal in the same ambient temperature. Ratio of emissivities of their surfaces is 1 : 2, ratio of their specific heats is 2 : 3, ratio of their radii is 2 : 1 and ratio of their densities is 1 : 3. Then ratio of their initial rate of cooling is