Lillian works on an assembly line and gets paid $15.00 for every hour of work. Payday is every Friday. Lillian makes more money if she works more hours, but if she is out sick, she does not get paid. Lillian is reinforced on what schedule? a. fixed interval schedule. a. fixed interval schedule. b. variable interval schedule. b. variable interval schedule. c. fixed ratio schedule. c. fixed ratio schedule. d. variable ratio schedule