Need help on this pls

Supongamos que estás estudiando dos estrellas. ambas estrellas tienen la misma magnitud aparente, pero la estrella a tiene una magnitud absoluta mayor que la estrella b. ¿que puedes decir acerca de la distancia a la tierra de estas dos estrellas?

In what environment would mineral formation caused by high pressures and high temperatures most likely occur?

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.