Resposta - Relatório de funcionários

Classe Employee:

namespace exercise89.Models;

internal class Employee
{
    public virtual string GenerateReport()
    {
        return "General report";
    }
}

Classe Manager:

namespace exercise89.Models;

internal class Manager : Employee
{
    public override string GenerateReport()
    {
        return "Manager's report: supervises the team.";
    }
}

Classe Developer:

namespace exercise89.Models;

internal class Developer : Employee
{
    public override string GenerateReport()
    {
        return "Developer report: writes code and fixes bugs.";
    }
}

Instâncias:

using exercise89.Models;

Employee employee1 = new Manager();
Employee employee2 = new Developer();

Console.WriteLine(employee1.GenerateReport());
Console.WriteLine(employee2.GenerateReport());