The Einstein frequency is often expressed in terms of an equivalent temperature E, where E= hv/k, Confirm

The Einstein frequency is often expressed in terms of an equivalent temperature θE, where θE= hv/k, Confirm that θE has the dimensions of temperature, and express the criterion for the validity of the high-temperature form of the Einstein equation in terms of it. Evaluate θE for
(a) Diamond, for which V= 46.5 THz and
(b) For copper, for which V= 7.15 THz. What fraction of the Dulong and Petit value of the heat capacity does each substance reach at 25°C?