407.  Which one of the following statements is correct? Copper and silicon are forming a junction; at thermal equilibrium
A. the Fermi levels in the two materials are at the same energy level irrespective of the number of free electrons in copper and silicon
B. the Fermi level of copper is at a higher energy level compared to that of silicon as copper has more free electrons.
C. the Fermi levle of silicon is at a higher energy level compared to that of copper as silicon has more free electrons.
D. copper and silicon, being in thermal equilibrium, will have the same pecific heat and Fermi levels have no relation to thermal equilibrium

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