Depending on the size of a solid particle, the gas behaves like particles (Epstein law, regime (1)), viscous fluid (Stokes law, regime (II)), or ideal fluid (regime (III)). Find the radius of a particle on the boundary between the regime (1) and regime (II) and that on the boundary between the regime (II) and the regime (III) when a solid particle is located at 5AU in the Hayashi model.