sentences:  [Notes 2]
  
  As far back as the 1970s, international fast food restaurant chain Burger King has attempted to introduce a premium line of burgers.These sandwiches are part of a system which eventually became known as the barbell strategy; a plan designed to expand Burger King's menu with both more sophisticated, adult-oriented fare along with products that are more value-oriented.This program is intended to bring in a larger, more affluent adult audience who will be willing to spend more on the better quality products on one side while maintaining a lower cost value menu dedicated to a more cost-conscious audience on the other.