World Bank data on a developing country shows per capita incomes of $4,900 for urban residents and $3,650 for rural residents. Migration from rural to urban areas has slowed the growth of urban incomes to a 3.0% average annual rate while rural per capita incomes grew 4.8% annually. If the historic growth rates continue into the future, how many years will it take for incomes to equalize? a. 14 years b. 17 years c. 19 years d. 20 years e. 23 years.