If Sample class has a Length property with get accessor then which of the following statements will work correctly?

1. A class can implement multiple interfaces.
2. Structures cannot inherit a class but can implement an interface.
3. In C#.NET, : is used to signify that a class member implements a specific interface.
4. An interface can implement multiple classes.
5. The static attribute can be used with a method that implements an interface declaration.

1. Data
2. Class
3. Enum
4. Structure
5. Namespace

namespace CuriousTabConsoleApplication
{ 
    class SampleProgram
    { 
        static void Main(string[] args)
        { 
            int[]arr = newint[]{ 1, 2, 3, 4, 5 }; 
            fun(ref arr);
        }
        static void fun(ref int[] a)
        { 
            for (int i = 0; i < a.Length; i++)
            { 
                a[i] = a[i] * 5; 
                Console.Write(a[ i ] + " "); 
            } 
        } 
    } 
}