Airline frequent flyer programs that reward customers with a free flight after every 25,000 miles of travel illustrate the use of a schedule of reinforcement.

The airline illustrates the use of FIXED-RATIO schedule of reinforcement.

Explanation: A fixed ratio schedule of reinforcement is technique of behavior modification through positive and negative reinforcement in which a response is rewarded only when reaching a specified number of responses. In this case, the response required is 25000 miles by the airline in order to be rewarded with a free flight.

your answer would b. the missisipi river

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