For the following reaction at 25°C, 5Fe2+(aq) + MnO4^-(aq) + 8H+(aq) ⇌ 5Fe3+(aq) + Mn2+(aq) + 4H2O(l), calculate (a) the standard potential, (b) the equilibrium constant, and (c) the potential under these conditions: [Fe2+] = 0.50 M, [Fe3+] = 0.10 M, [MnO4^-] = 0.025 M, [Mn2+] = 0.015 M, and a pH of 7.00.