Adelen how would I write a for loo that computes the sum of first n positive integers. Set the variable n to 12 and print "The sum of all integers

Adelen how would I write a for loo that computes the sum of first n positive integers. Set the variable n to 12 and print "The sum of all integers from 0-12 is " + sum?

Also a for loop that prints 1 through n, separated by commas. Example: for n = 9 print 1, 2, 3, 4, 5, 6, 7, 8, 9?  These are also in C#

usingusingusingusing System;System.Collections.Generic;System.Linq;System.Text; namespace ConsoleApplication1{class Program1{static void Main(string args){int n = 9;/*for loop that...