Brain drain is the loss of __________ to richer countries

Democracy usually fails in countries with per capita GDPs of less than __________ and succeeds in countries with per capita GDPs of more than __________

a. $3,000; $5,000 b. $6,000; $10,000 c. $10,000; $30,000 d. $20,000; $40,000

A neighborhood uses well water, and no individual family has to pay for the water they consume. Thus, each family waters their grass excessively and doesn't bother to conserve water. The well runs dry. This is an example of the economic model known as

a. the tragedy of the commons. b. the Prisoner's Dilemma. c. the chicken game. d. the overabundance problem.