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Which barrier to economic development is shown in the following examples? i. the high rate of hiv infection in underdeveloped nations ii. the use of children as soldiers in uganda’s army in the early 2000s iii. low literacy rates in underdeveloped nations with limited exposure to adequate education a. foreign debt b. political instability c. widespread disease d. low levels of social welfare

All of the following occurred due to the invention of the railroad except

Pollution from one country can affect another. for example, south korea is especially affected by pollution and dust storms that come from