Note: As Mike Yassa, the lead author on the study, pointed out to me, the study did not actually test whether consuming caffeine before a task enhances memory, the problem being that other confounding factors can then lead to difference in performances on the test.
The US debt is more than $20.1 trillion, the largest in the world. Here are the 3 reasons it grew so large, and how it damages U.S. economic growth. The US debt is more than $20.1 trillion, the largest in the world.
The US has a gross foreign debt of $18.4 trillion and a net foreign debt of over $3 trillion for 2010. The US has a gross foreign debt of $18.4 trillion and a net foreign debt of over $3 trillion for 2010, where net foreign debt is defined as the countryâs borrowings from the rest of the world, less the countryâs lending to the rest of the world. The US has lent the world $15.3 trillion in the years when it was the sole economic superpower.