thanks in advance.

The critical temperature and pression of CO2 are Tc=304.2K and pc=72.8atm, respectively. Assuming that the gas can be described by the van der Waals model, then: (a) Determine the fugacity coefficient at 10atm and 40C. [The relations between the critical parameters and the gas parameters a and b are b=RTc/(8pc) and a=27R2Tc2/(64pc).] (b) Use the Lewis-Randall rule to determine the fugacity of CO2 in a mixture of 0.7mol of CO2 and 1.2mol of N2 at 40C and 10atm. (Discuss all the assumptions made.)