public class Circle
{
public static double PI = 3.141592653589793;
private double radius;
public Circle(double radius)
{
this.radius = radius;
}
public static double CalculateSurface(double radius)
{
return (PI * radius * radius);
}
public void PrintSurface()
{
double surface = CalculateSurface(radius);
Console.WriteLine("Circle's surface is: " + surface);
}
}
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