Final answer:
The art portion of the dental model should occupy no more than one-third of the overall model size. To ratify an amendment, three-fourths of states must agree for it to become law.
Step-by-step explanation:
The art portion of the dental model should be no more than one-third of the overall size. This answer is related to dental models, which are often used in the context of dental studies, part of the broader health sciences field.
As for the question about ratification of an amendment, the United States Constitution requires that to ratify an amendment, three-fourths of the states must agree before it becomes law. Therefore, the correct answer to this question is B) three-fourths.