I think it’s a&c. I could be wrong, but at least try
Answer:
Density is an intensive property. This means that regardless of the object's shape, size, or quantity, the density of that substance will always be the same. ... It is because density in an intensive property of matter. So they are not considered properties.
Explanation:
The porcupine is a rodent with an unusual trait. Porcupines have sharp spines or quills that help protect it against its predators. This trait is different from other rodents because of its needle like quills. This animal is also similar to that of a hedgehogs.
The correct answer is; the open mouth of a baby robin is seen as a sign stimulus for the female robin (parent), and that the open mouth is the impending cause for her behavior.
