Anchor: Such a machine might have an optical character reader and might put on a barcode.
Entailed: An optical character reader might be on such a machine.
Contradiction: No machine is expected to contain an optical character reader. 
Contradiction: They are sitting in class.
Contradiction: A person standing at a cave surrounded by rocks outdoors.
Contradiction: The beginning of Tim's speech.
Contradiction: He was able to see inside the material due to the slits.