The following mixture of hydrocarbons is obtained as one stream in a petroleum refinery on a mole basis: 5% ethane, 10% propane, 40% n-butane, 45% isobutane. Assuming the shortcut K-ratio model: 

(a) Compute the bubble point of the mixture at 5 bar; 

(b) Compute the dew point of the mixture at 5 bar; 

(c) Find the amounts and compositions of the vapor and liquid phases that would result if this mixture were to be isothermally flash vaporized at 30°C from a high pressure to 5 bar.