[Solved] An inverter is a digital circuit which takes a digtal input and produces an output which is the opposite state of the input. Hormones: null Observations: The act of noticing or perceiving something and registering it as being significant, often used in research and studies for data collection. Pornographic Magazines: Printed publications containing images and texts intended to stimulate erotic feelings rather than convey art or education. Psychologist: A professional trained in the study of the mind and behavior, often providing therapy and counseling.