Resposta - Execução de Tarefas Agendadas

Classe ScheduledTask:

namespace exercise91.Models;

internal abstract class ScheduledTask
{
    public abstract void Execute();
}

Classe TaskBackup:

namespace exercise91.Models;

internal class TaskBackup : ScheduledTask
{
    public override void Execute()
    {
        Console.WriteLine("Performing system backup task...");
    }
}

Classe TaskCleaning:

namespace exercise91.Models;

internal class TaskCleaning : ScheduledTask
{
    public override void Execute()
    {
        Console.WriteLine("Cleaning up temporary server files...");
    }
}

Classe TaskReport:

namespace exercise91.Models;

internal class TaskReport : ScheduledTask
{
    public override void Execute()
    {
        Console.WriteLine("Generating and sending daily reports...");
    }
}

Instâncias:

using exercise91.Models;

List<ScheduledTask> tasks = new List<ScheduledTask>
{
    new TaskBackup(),
    new TaskReport(),
    new TaskCleaning()
};

foreach (ScheduledTask task in tasks)
{
    task.Execute();
}