PLEASE HELP ME :)

Consider two objects: (a) a metal, thin sphere with a radius R and mass M, and (b) a "riddled sphere" obtained from the same sphere as sphere (a) by drilling identical small holes so that the remaining surface is 4πR2 / and mass (b) is equal to M / 2. The holes are uniformly distributed, their radius is much smaller than R, but at the same time considerably larger than the thickness of the sphere. How often will the rate of cooling of the object (b) be greater (or less) than the rate of cooling of the object (a) if we place each of them individually in an empty space when their temperature is T = 300 K? Treat each object as a perfectly black and perfectly conductive body. Skip the fact that some of the waves emitted by the objects under consideration are longer than the holes in the sphere (their contribution to the energy balance is negligible).
Thanks for your answers
Monika from POLAND