a. Determine the ratio of thermal conductivity for N 2 ( = 0.43 nm 2 ) at

a. Determine the ratio of thermal conductivity for N₂(σ = 0.43 nm²) at sea level (T = 300.K, P = 1 atm) versus the lower stratosphere (T = 230.K, P = 0.25 atm).

b. Determine the ratio of thermal conductivity for N₂ at sea level if p = 1atm, but the temperature is reduced to 100. K versus the lower stratosphere. Which energetic degrees of freedom will be operative at the lower temperature, and how will this affect C_V,m?