private void btnCalc_Click(object sender, EventArgs e)
 {
     if (radInsured.Checked)
     {
         patient = new InsuredPatient()
         {
             Name = txtName.Text, HoursInHospital = Convert.ToInt32(numHours.Value)
         };
     }
     else
     {
         patient = new Patient()
         {
             Name = txtName.Text, HoursInHospital = Convert.ToInt32(numHours.Value)
         };
     }
     lblOutput.Text = patient.ShowInfo();
 }