Positive economics statements are testable

If more firms chose to pay efficiency wages, which of the following would shift to the right?

a. both the long-run Phillips curve and the long-run aggregate supply curve b. the long-run Phillips curve but not the long-run aggregate supply curve c. the long-run aggregate supply curve but not the long-run Phillips curve d. neither the long-run Phillips curve nor the long-run aggregate supply curve

In the market for labor, the monopsonist is the sole:

A. buyer and can keep wages up, above the competitive wage. B. seller and can push wages down, below the competitive wage. C. buyer and can push wages down, below the competitive wage. D. seller and can keep wages up, above the competitive wage.