Which of the following is/are generally regarded as true statements:
1. Some individual differences are a result of being at a particular state of development.
2. Language and thought develop independently.
3. Certain learning tasks are virtually impossible for individuals at an early stage of cognitive development.
4. Mental models are directly observable markers of development.
5. The concepts of a more knowledgeable other and the zone of proximal development are closely related.
6. Development theorists are engaged in descriptive research—describing how individuals develop rather than how individuals should develop
