Engineers, who were the leaders of the Underground Railroad, helped slaves who were running away by providing them with food, shelter, and sometimes jobs. They hid the slaves from people who were trying to catch them and return them to slavery.
The GDP per Capita, in Nigeria, when adjusted by Purchasing Power Parity is equivalent to 32 percent of the world's average.
Nigeria ranks number 7 in the list of countries (and dependencies) by population. The population density in Nigeria is 211 per Km2 (545 people per mi2). The total land area is 910,802 Km2 (351,662 sq. miles) 49.9 % of the population is urban (95,764,092 people in 2017) The median age in Nigeria is 18 years.