private void button5_Click(object sender, EventArgs e)
        {
            RegistrarAlumno b2 = new RegistrarAlumno(u);

            b2.Show();
            this.Hide();
        }
        private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            RegistrarAlumno b2 = new RegistrarAlumno(u);

            b2.Show();
            this.Hide();
        }