Compressibility factor for a given vapour or gas can be represented by

(a) \(Z=1+B^{\prime} P+C^{\prime} P^{2}+D^{\prime} P^{3}+\cdots\)

(b) \(Z=1+\frac{B}{V}+\frac{C}{V^{2}}+\frac{D}{V^{3}}+\cdots\)

(c) Either

(a) or (b)

(d) None of these