Final answer:
The statement is false. In a variable-interval schedule, reinforcement is presented after varying, unpredictable amounts of time, not a specific one.
Step-by-step explanation:
The statement that in a variable-interval schedule the reinforcement is presented after a specific amount of time is false. In a variable-interval schedule, reinforcement is given to a person or animal after varying, unpredictable amounts of time have passed. This is different from a fixed interval reinforcement schedule, where reinforcement is provided after a set, constant amount of time. An example of a variable-interval schedule could be the way a fast-food restaurant manager, Manuel, never knows when the quality control visit will happen, but if the restaurant is up to standard when it does, his staff receives a bonus.