When collecting data to conduct research, if the sample used includes only observations which have remained in the sample over time, making that sample unrepresentative of the broader population, ________ occurs.

If real GDP is $13,000 billion and aggregate hours are 270 billion, labor productivity equals

A) $6.50 per hour. B) $45 per hour. C) $48 per hour. D) $650 per hour.

The Bretton Woods exchange rate system was a

A) fixed exchange rate system. B) floating exchange rate system. C) flexible exchange rate system. D) managed float exchange rate system.