What signifies the period known as prehistory?
a. language was fully evolved.
b. writing was very elementary.
c. there was no form of writing.
d. records were hidden away.

Prior to the presence of europeans on the continent, the slave trade in africa a) did not exist in any form. b) was limited to internal trade only. c) included the trans-saharan and indian ocean slave trade. d) was rarely needed due to the lack of an agricultural economy.

The first map shows colonial powers and their holdings (1945). the second map shows human development worldwide. compare the two maps. what do the maps indicate about regions that gained independence in the second half of the twentieth century? they differ in their development patterns. they are as developed as their colonial powers. they are more developed than their colonial powers. they remain less developed than their colonial powers.

Why did einstein write a letter to president roosevelt