A vapor/liquid experiment for the carbon disulfide(1) + chloroform(2) system has provided the following data at 298 K: P₁^sat = 46.85 kPa, P₂^sat = 27.3 kPa, x₁ = 0.2, y₁ = 0.363, and P = 34.98 kPa. Estimate the dew pressure at 298 K and y₁ = 0.6, using

(a) The Scatchard-Hildebrand model with k₁₂ = 0

(b) The SSCED model with a default value of k₁₂

(c) The SSCED model with k₁₂ matched to the data

(d) The van Laar equation