1 is 0n I believe 2 8n or 2n 3 would be 10n 4 is 0n or 12n
Primary Circular Reactions (1-4 months): This substage involves coordinating sensation and new schemas. For example, a child may suck his or her thumb by accident and then later intentionally repeat the action. These actions are repeated because the infant finds them pleasurable.
It takes the shape of the cup and it can be sucked through a straw
