One would generally be correct in saying that patents typically help producers of a product more than its consumers, while trademarks typically help both consumers and producers of a product.

Explain the rationale behind this statement in a few sentences.

Does this or does this not help explain why patents are only granted for 20 years while trademarks are granted for an unlimited duration? Explain.

Consider the policy that states that if a trademark becomes a commonplace descriptor of a product (like “escalator” or “zipper”), the trademark becomes invalid. Is this wise economically? Explain.