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Question 5 4 pts On a production possibility graph. an efficient level of production is O Any combination on the line. Only producing one good and never a combination of both. O When the product is produced at the lowest price possible. Where both goods are produced an equal amount of time.Question 6 4 pts If Joe can produce either 10 sandwiches or 15 burgers per hour. His opportunity cost of sandwiches is 10 sandwiches O 15 burgers O 0.67 sandwiches 1.5 burgers