around 1970, ed malagodi noted that rhesus monkeys would not press a lever more than 200 times to earn food (banana pellets). he changed things up and decided to flash a red stimulus light for 1-second right before he delivered the food. after that pairing, when the monkey completed a fr-100, the red light flashed but no banana pellets were delivered. in this experiment, the animal had to complete a fr 100 for each red light flash and on the fifth flash the monkey also got a banana pellet (so - the animal had to complete five fr 100 response schedules before getting food). now - they emitted 500 responses easily (whereas before they would give up if you asked them for 200 responses per pellet). how would you classify the stimulus of the red light?