Molar volume (Vₘ) of a van der Waals gas can be calculated by expressing the van der Waals equation as a cubic equation with Vₘ as the variable. The ratio (in mol dm⁻³) of the coefficient of Vₘ² to the coefficient of Vₘ for a gas having van der Waals constants a = 6.0 dm⁶ atm mol⁻² and b = 0.060 dm³ mol⁻¹ at 300 K and 300 atm is _____. Use: Universal gas constant (R) = 0.082 dm³ atm mol⁻¹ K⁻¹