What factors were behind the scramble for africa and what impact did it have on the continent?

Ineed to have answers for numbers 2-4 reply to this question

What deadly disease cost many workers their lives before dr. william gorgas found a treatment?

Why did many americans want the united states to cuba gain independence from spain? cuba was rich in natural resources, including gold and oil. cuba would provide access to the pacific ocean through a narrow strait. the united states had strong economic ties to cuba. the majority of cubans expressed interest in becom ing a us state.