Complete the missing c# code in the bellow program required to obtain the following expected result:

Welcome to c# workshops & training

Registration cost varies according to the number of days as follows:

The cost for 5 days is $200

The cost for 10 days is $500

The cost for 15 days is $1000

Note: You have to comply with the instructions given as comments in the program

using System;

class Program {

public class workshop {

int nbOfdays;

decimal fees;

public workshop(int ndays, decimal fe) { nbOfdays = ndays; fees = fe; }

public override string ToString() {

// use interpolated string

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}

public static void Main(String[] args) {

String str1 = "Welcome to", str2 = "c# workshop & training", str3 = "Registration cost";

workshop[] workshops = { new workshop(5, 200), new workshop(10, 500), new workshop(15,1000) };

// printing using formatting string and the defined string variables

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// printing using interpolated string and the defined string variables

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// printing all workshops using foreach

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Console.ReadKey();

}

}