Ethylene is liquefied by a throttle cooling device (an insulated valve). The entering conditions are 60 bar and 26.85C and leaves at 10 bar. (a) Set up a thermodynamic path and derived the expressions required to evaluate the thermodynamics properties needed in this problem assuming that ethylene can be described by the Redlich-Kwong equation of state. For example, if you choose the departure function path approach, then you have to derive the necessary departure functions to solve this problem. (b) Using the solution strategy of part (a), calculate the fraction of the inlet stream that is liquefied according to properties estimated from the Redlich-Kwong equation of state