In a copper crystal, assume that the atoms interact with each other through the first and the second nearest neighbors. The interaction energy per nearest neighbor bond is ε1 and the second nearest neighbor ε2.At the room temperature, the equilibrium (single) vacancy concentration ismeasured at 2×10-5; and at the elevated temperature close to melting point, the vacancy concentration is 10-4. What are the vacancy formation energy and the bond energy ε1 and ε2?