Answer : The dipole-dipole interaction.
Explanation : The kind of bond that is created by a weak electrical attraction between two polar molecules is dipole-dipole interaction.
The type of force which occurs between the positive end of one molecule and the negative end of another molecule: is dipole-dipole interaction.
For better understanding, please refer the attachment.
Timbuktu was considered a MASSIVE trade center in Mali. That is how all of the foreign goods came into the kingdom. It also had education centers which was very important in Mali.