relative saturation

Air at 345 K has a dew-point temperature of 312 K. Calculate the absolute and relative humidity, and the enthalpy of the mixture relative to liquid water and air at 273 K, in H/kg of dry air.
2 Calculate the absolute humidity, relative saturation, and dew-point temperature of a mixture of benzene-nitrogen at a pressure of 1.5 bar and temperature of 320 K if the partial pressure of benzene in the mixture is 0.2 bar