I am getting the following output when this program is run: Please enter the Social Security Number for taxpayer 0: 111111111 Please enter the gross income for taxpayer 0: 20000 Please enter the Social Security Number for taxpayer 1: 555555555 Please enter the gross income for taxpayer 1: 50000 Please enter the Social Security Number for taxpayer 2: 333333333 Please enter the gross income for taxpayer 2: 5464166 Please enter the Social Security Number for taxpayer 3: 222222222 Please enter the gross income for taxpayer 3: 645641 Please enter the Social Security Number for taxpayer 4: 444444444 Please enter the gross income for taxpayer 4: 29000 Taxpayer # 1 SSN: 111111111, Income is $20,000.00, Tax is $0.00 Taxpayer # 2 SSN: 555555555, Income is $50,000.00, Tax is $0.00 Taxpayer # 3 SSN: 333333333, Income is $5,464,166.00, Tax is $0.00 Taxpayer # 4 SSN: 222222222, Income is $645,641.00, Tax is $0.00 Taxpayer # 5 SSN: 444444444, Income is $29,000.00, Tax is $0.00 Unhandled Exception: System.InvalidOperationException: Failed to compare two elements in the array. --- System.ArgumentException: At least one object must implement IComparable. at System.Collections.Comparer.Compare(Object a, Object b) at System.Collections.Generic.ObjectComparer`1.Compare(T x, T y) at System.Collections.Generic.ArraySortHelper`1.SwapIfGreaterWithItems(T[] keys, IComparer`1 comparer, Int32 a, Int32 b) at System.Collections.Generic.ArraySortHelper`1.QuickSort(T[] keys, Int32 left, Int32 right, IComparer`1 comparer) at System.Collections.Generic.ArraySortHelper`1.Sort(T[] keys, Int32 index, Int32 length, IComparer`1 comparer) --- End of inner exception stack trace --- at System.Collections.Generic.ArraySortHelper`1.Sort(T[] keys, Int32 index, Int32 length, IComparer`1 comparer) at System.Array.Sort[T](T[] array, Int32 index, Int32 length, IComparer`1 comparer) at System.Array.Sort[T](T[] array) at Assignment5.Taxpayer.Main(String[] args) in Program.cs:line 150 Notice the 0s at the end of the line that should be the tax amount??? Here is the code: using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace taxes { class Rates { // Create a class named rates that has the following data members: private int incLimit; private double lowTaxRate; private double highTaxRate; // use read-only accessor public int IncomeLimit { get { return incLimit; } } public double LowTaxRate { get { return lowTaxRate; } } public double HighTaxRate { get { return highTaxRate; } } //A class constructor that assigns default values public Rates() { int limit = 30000; double lowRate = .15; double highRate = .28; incLimit = limit; lowTaxRate = lowRate; highTaxRate = highRate; } //A class constructor that takes three parameters to assign input values for limit, low rate and high rate. public Rates(int limit, double lowRate, double highRate) { } // A CalculateTax method that takes an income parameter and computes the tax as follows: public int CalculateTax(int income) { int limit = 0; double lowRate = 0; double highRate = 0; int taxOwed = 0; // If income is less than the limit then return the tax as income times low rate. if (income < limit) taxOwed = Convert.ToInt32(income * lowRate); // If income is greater than or equal to the limit then return the tax as income times high rate. if (income >= limit) taxOwed = Convert.ToInt32(income * highRate); return taxOwed; } } //end class Rates // Create a class named Taxpayer that has the following data members: public class Taxpayer { //Use get and set accessors. string SSN { get; set; } int grossIncome { get; set; } // Use read-only accessor. public int taxOwed { get { return taxOwed; } } // The Taxpayer class should be set up so that its objects are comparable to each other based on tax owed. class taxpayer : IComparable { public int taxOwed { get; set; } public int income { get; set; } int IComparable.CompareTo(Object o) { int returnVal; taxpayer temp = (taxpayer)o; if (this.taxOwed > temp.taxOwed) returnVal = 1; else if (this.taxOwed < temp.taxOwed) returnVal = -1; else returnVal = 0; return returnVal; } // End IComparable.CompareTo } //end taxpayer IComparable class // **The tax should be calculated whenever the income is set. // The Taxpayer class should have a getRates class method that has the following. public static void GetRates() { // Local method data members for income limit, low rate and high rate. int incLimit = 0; double lowRate; double highRate; string userInput; // Prompt the user to enter a selection for either default settings or user input of settings. Console.Write("Would you like the default values (D) or would you like to enter the values (E)?: "); /* If the user selects default the default values you will instantiate a rates object using the default constructor * and set the Taxpayer class data member for tax equal to the value returned from calling the rates object CalculateTax method.*/ userInput = Convert.ToString(Console.ReadLine()); if (userInput == "D" || userInput == "d") { Rates rates = new Rates(); rates.CalculateTax(incLimit); } // end if /* If the user selects to enter the rates data then prompt the user to enter values for income limit, low rate and high rate, * instantiate a rates object using the three-argument constructor passing those three entries as the constructor arguments and * set the Taxpayer class data member for tax equal to the valuereturned from calling the rates object CalculateTax method. */ if (userInput == "E" || userInput == "e") { Console.Write("Please enter the income limit: "); incLimit = Convert.ToInt32(Console.ReadLine()); Console.Write("Please enter the low rate: "); lowRate = Convert.ToDouble(Console.ReadLine()); Console.Write("Please enter the high rate: "); highRate = Convert.ToDouble(Console.ReadLine()); Rates rates = new Rates(incLimit, lowRate, highRate); rates.CalculateTax(incLimit); } } static void Main(string[] args) { Taxpayer[] taxArray = new Taxpayer[5]; Rates taxRates = new Rates(); // Implement a for-loop that will prompt the user to enter the Social Security Number and gross income. for (int x = 0; x < taxArray.Length; ++x) { taxArray[x] = new Taxpayer(); Console.Write("Please enter the Social Security Number for taxpayer {0}: ", x + 1); taxArray[x].SSN = Console.ReadLine(); Console.Write("Please enter the gross income for taxpayer {0}: ", x + 1); taxArray[x].grossIncome = Convert.ToInt32(Console.ReadLine()); } Taxpayer.GetRates(); // Implement a for-loop that will display each object as formatted taxpayer SSN, income and calculated tax. for (int i = 0; i < taxArray.Length; ++i) { Console.WriteLine("Taxpayer # {0} SSN: {1}, Income is {2:c}, Tax is {3:c}", i + 1, taxArray[i].SSN, taxArray[i].grossIncome, taxRates.CalculateTax(taxArray[i].grossIncome)); } // end for // Implement a for-loop that will sort the five objects in order by the amount of tax owed Array.Sort(taxArray); Console.WriteLine("Sorted by tax owed"); for (int i = 0; i < taxArray.Length; ++i) { Console.WriteLine("Taxpayer # {0} SSN: {1}, Income is {2:c}, Tax is {3:c}", i + 1, taxArray[i].SSN, taxArray[i].grossIncome, taxRates.CalculateTax(taxArray[i].grossIncome)); } } //end main } // end Taxpayer class } //end Any clues as to why the dollar amount is coming up as 0 and why the sort is not working?