Using the law of equipartition of energy, obtain a relation between the degrees of freedom and specific heat ratio of a polyatomic gas:
a) γ = 1 + (2/ℓ)
b) γ = 1 + (2/ℓ)RT
c) γ = 1 + (2/ℓ)RT/P
d) γ = 1 + (2/ℓ)P/RT