"Broker Carr, with ABC Real Estate Company, listed the property of a seller. Broker Smith, with XYZ Real Estate Company, called Broker Carr, and disclosed that he was a Buyer Agent. Broker Smith wrote a contract with a buyer for the sale of the property. What, if any, is the relationship between the buyer's broker, the seller and the listing broker?

The prebisch–singer hypothesis concludes that: a. technology lowers the cost of manufactured products, so developing countries should see an increase in their terms of trade. b. developing countries experience a long-run decline in their terms of trade, as the demand for primary products in higher-income countries declines relative to their demand for manufactured goods. c. because of unfair trading practices, labor in developing countries is exploited. d. opec has been responsible for a slowdown in the world's standard of living.