Answer:
1) The child who has just begun understanding that when her toy rolls under the sofa, out of sight, it is still there is most likely in the Sensorimotor period stage of development, according to Piaget's theory of cognitive development.
2) The statement that is most likely to indicate that Chandra is a person who would score high on Neuroticism is: "Chandra is always worried and can be quite insecure and self-conscious."