Why had Africa remained isolated and untouched by European powers for so long?

By the 1880s European powers were interested in Africa's resources, particularly mineral wealth and forests. Today Africa is divided into 53 independent countries but may scholars argue that the boundaries that separate these countries are really artificial. They were drawn by Europeans at the Berlin Conference in 1884-85 without a single African present. They did not divide the continent by cultural or tribal region, but instead created borders based on their own interests. The problems this created separating families, language groups, trading partners, pastoralists from watering holes, etc. are still very much at issue today.

taking a bath requires the most water out of the given options because it takes a significant amount of water in order to fill a bathtub.