Part 2, a general reference section, includes the following: Currencies around the world ; Birthstones ; Wedding anniversaries ; South African prime ministers (presidents) ; The seven wonders of the world ; Geograhical facts: principal mountains of the world, principal rivers of the world, principal deserts of the world, the highest waterfalls of the world, principal oceans and seas of the world, principal islands of the world, principal active volcanoes of the world and the continents ; The official languages of the world.