Final answer:
A café offering a punch card exemplifies the use of a fixed-ratio schedule of reinforcement. Each time a patron purchases a beverage, a hole is punched, and when ten holes are punched, the patron receives a free beverage.
Step-by-step explanation:
The promotion that exemplifies the use of a fixed-ratio schedule of reinforcement is a café offering a punch card. Each time a patron purchases a beverage, a hole is punched, and when ten holes are punched, the patron receives a free beverage. This is an example of a fixed ratio reinforcement schedule because a set number of responses, in this case, the purchase of ten drinks, must occur before the behavior of the patron is rewarded with a free beverage.