Islam was introduced into west africa by

missionaries.
prophets.
traders.
nomads.

The correct answer is: traders. The expansion of Islam in this region was peaceful, slow and progressive, there was no need to use violence and the main tool for its dissemination was the commercial networks. With the introduction of Islam literacy was increased because people needed to know how to read to be devout practitioners.

united states reinforcements contributed greatly to three allied victories in france at: cantigny (first major american battle), argonne (the largest in the united states military history, involving 1.2 million american soldiers), and château-thierry (one of the first actions under general pershing).