Try this:
using System;
class circle
{
public static void Main()
{
float radius = 12.5F;
float circumfrence, area;
float pi = 3.1487F;
circumfrence = 2 * pi * radius;
area = pi * radius * radius;
Console.WriteLine("The Radius of the circle = " + radius);
Console.WriteLine(""); //Blank Line
Console.WriteLine("Its Circumfrence = " + circumfrence);
Console.WriteLine("Its Area = " + area);
Console.ReadLine();
}
}