The molar internal enegry of a gas over a temperature range is expressed as: `U_(m) (T) =a +bT +cT^(2)`, where `b = 16 J mol^(-1)K^(-1)`and `c = 6 xx 10^(-3) J mol^(-1)K^(-2)`. Find:
a. `C_(V,m)at 300K`
b. The entropy change when `1 mol` of a gas is heated from `300K` to `600K` at constant volume.