Array List

Clase abstractcurso
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace CasoArreglos.modelo
{
abstract class AbstractCurso
{public const int N = 50;
protected Alumno[] lista;
protected int contAlumnos;

public int ContAlumnos
{
get { return contAlumnos; }
}public AbstractCurso()
{
this.lista = new Alumno[N];
this.contAlumnos = 0;
}

public abstract int AgregarAlumno(Alumno a);
publicabstract Alumno[] ObtenerLista();
public abstract int Mediana();
public abstract int Media();
public abstract int Moda();
public abstract Alumno Mayor();public abstract int Menor();
public abstract int Aprobados();
public abstract int Desaprobados();

}
}

Clase alumno
using System;
using System.Collections.Generic;
usingSystem.Linq;
using System.Text;

namespace CasoArreglos.modelo
{

class Alumno
{
private String nombre;

public String Nombre
{
get { return nombre;}
set { nombre = value; }
}
private int pract1;

public int Pract1
{
get { return pract1; }
set { pract1 = value; }}
private int pract2;

public int Pract2
{
get { return pract2; }
set { pract2 = value; }
}
private int pract3;public int Pract3
{
get { return pract3; }
set { pract3 = value; }
}
private int examen;

public int Examen
{
get {return examen; }
set { examen = value; }
}

public int PromPract()
{
int pp;
pp = (pract1 + pract2 + pract3) / 3;
return...