In a two country world, at least one country must lose from trade

Which of the following are TRUE regarding "positive" statements? I. They describe what "ought to be." II. They describe what is believed about how the world appears. III. They can be tested as to their accuracy

A) I and II B) II and III C) I and III D) I, II and III

Expectations are taken to be rational in ________

A) traditional Keynesian and new Keynesian theory B) new Keynesian and real business cycle theory C) real business cycle and traditional Keynesian theory D) traditional Keynesian, new Keynesian and real business cycle theory