Eco-Clean Inc. v Brown Assignment

Read the case Eco-Clean Inc. v Brown (p. 493-4 in your textbook), a case in which the court decided an agency relationship did exist.

1. Could an express agency relationship have existed in this case? What would have had to happen?
2. Could an implied agency relationship have existed in this case? What would have had to happen?
3. Could an agency by ratification have existed in this case? What would have had to happen?
4. Could an apparent agency have existed in this case? What would have had to happen?