Object permanence is the developmental milestone that must be reached before an infant experiences separation anxiety. It is used to describe the ability of a child to know that objects continue to exist despite the fact that they can no longer be perceived that is , seen or heard, touched, smelled, or sensed in any way. This milestone is developed through touching and handling objects by the infants.
5: true
6: Oxygen
7: H+
8: true
Answer: Characteristics: The fins are supported by rays, as the name indicates. In contrast to the cartilaginous fish they have a rigid skeleton. The swim bladder is also a unique feature of most ray-finned fish, enabling them to maintain buoyancy as they move up or down in the water.
So it could fit perfectly.