Gaseous State

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 mol‌dm−3 ) of the coefficient of Vm2 to the coefficient of Vm for a gas having van der Waals constants a=6.0dm6‌atm‌mol−2 and b=0.060dm3mol−1 at 300K‌and ‌300‌atm is _____.
Use: Universal gas constant (R)=0.082dm3‌atm‌mol−1‌K−1