In an analytical chemistry laboratory, a student determines the concentration of iron in an aqueous solution by titrating an acidified sample of \(\text{Fe}^{2+}\text{(aq)}\) with standard potassium dichromate, \(\text{K}_2\text{Cr}_2\text{O}_7\text{(aq)}\). During the titration, \(\text{Fe}^{2+}\text{(aq)}\) is oxidized to \(\text{Fe}^{3+}\text{(aq)}\) while \(\text{Cr}_2\text{O}_7^{2-}\text{(aq)}\) is reduced to \(\text{Cr}^{3+}\text{(aq)}\). Which of the following is the balanced net ionic equation for the reaction that occurs in the acidic solution?