Volume from Virial Equation of State  |POLVER05_1
f(v) = (R*T/P)*(1+b/v+c/v^2)-v  #
b = -159  #
c = 9000  #
P = 75  #
T = 430.85  #
R = 82.05  #
v(min)=100, v(max)=300