Find the critical constant `(P_(C),V_(C) and T_(C))` in terms of `A and B`, also find compressibility factor `(z)` for the following equation of state
`PV=R R-(A)/(V)+(2B)/(V^(2))`
where `A and B` are constants, P = pressure and V = molar volume. Hence, write the value of `(1)/(Z_(C))`.
