1. The problem statement, all variables and given/known data here's a problem I'm having a little bit of trouble with. A)The high temperature limit of the einstein model gives Cv = 3Nk, Find the next order correction in the high temperature limit. B)Show that the first correction to the specific heat in the debeye model in the low temperature limit is: 9Nk(theta/T)exp(-theta/T). C)Find an expression for the heat capacity of a two-dimensional square crystal in the debeye approximation. show that Cv is proportional to T^2 in the low temperature limit. I'm not sure how to start or approach this problem, any help with either of the parts would be greatly appreciated. 2. Relevant equations 3. The attempt at a solution my first thought was to use the summation or intergral of the energy to find the next order and then use Cv = dE/dT, but im not entirely sure how to set it up.