public void addScore()
      {
      if( level >= 1 && level <= 3 )
         {
         score += 5;
         } //end if
      if( level >= 4 && level <= 6 )
         {
         score += 10;
         } //end if
      if( level >= 7 && level <= 9 )
         {
         score += 25;
         } //end if
      if( level >= 10 )
         {
         score += 50;
         } //end if
      } //end addScore