Carlos trains a pigeon to peck a disk by reinforcing each disk peck. Once the response is learned, Carlos begins to cut back on the reinforcers. At first he reinforces every other response, then every third response, every fifth response, every tenth response, and so on. Carlos is using a procedure called .

Which of the following statements about early mesopotamian civilizations is false? a. mesopotamia was one of the first places in the world where urbanization occurred. b. mesopotamian civilizations settled between the tigris and euphrates rivers. c. mesopotamia was located in modern-day china. d. mesopotamian civilizations invented the wheel.