Which of the following statements are correct about the Stack collection?

1. It can be used for evaluation of expressions.
2. All elements in the Stack collection can be accessed using an enumerator.
3. It is used to maintain a FIFO list.
4. All elements stored in a Stack collection must be of similar type.
5. Top-most element of the Stack collection can be accessed using the Peek() method.

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 ] + " "); 
            } 
        } 
    } 
}