A sea lion at a zoo is trained to wave to a crowd of visitors. During training, the sea lion receives a fish each time she moves her flipper in a way that appears to be waving. The trainer also blows a whistle each time he gives the sea lion a fish. As the sea lion becomes more stable and advanced in her waves to the crowd, the trainer sometimes provides a fish and sometimes blows a whistle. There is no particular order or timing to when he provides a fish or blows the whistle. The trainer does not hit or yell at the sea lion as part of training
Describe whether the trainer is using classical or operant conditioning, or both. In your description of the training, use the language of learning theory, with concepts such as unconditioned stimulus (US), conditioned stimulus (CS), unconditioned response (UCR), conditioned response (CR), positive reinforcement, negative reinforcement, and punishment.

Identify the schedule of reinforcement the trainer is using (fixed ratio, variable ratio, fixed interval, variable interval). Defend your answer.