World history 1 I don’t know the answer I need help

Which physical feature minimizes population density in northern africa?

Jane determines x = 4 and y = 1 is the solution to the following system of equations.

1. discovered the new world balboa 2. explored the north american southwest hudson 3. his crew was the first to sail around the world vespucci 4. conquered the incas of peru cortes 5. discovered the pacific ocean columbus 6. conquered the aztecs of mexico cabot 7. discovered fishing grounds off newfoundland pizarro 8. looted spanish vessels for england drake 9. claimed the hudson river area for dutch coronado 10. priest who explored the mississippi marquette 11. man for whom the new world is named magellan