What caused european colonial powers to take interest in africa after the slave trade ended

The right answer is D.The European power did not create boundaries based on tribal divisions and forced rival tribes to live with each other.African's huge variety of languages and cultures discouraged unity among them. Wars fought between ethnic groups over land, water, and trade rights also prevented a unified stand. Europeans soon learned to play rival groups against each other. The competition between European nations was so fierce that they feared war among themselves. To prevent conflict, 14 European nations met at the Berlin Conference in 1884-85 to lay down rules for the division of Africa. The Europeans nations divided the continent with little regard about how Africans ethnic or linguistic groups were distributed. No African ruler was invited to attend their meetings, yet the Conference sealed Africa's fate.

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the answer is d. party organizers, volunteers, voters and elected officials.

the causes of the dust bowls were severe droughts,   lands became dry and hard, temperature was higher than usual, hot and dry conditions killed crops, high winds. because of those factors, the winds kicked up dry soil and created clouds of dust.