In what five ways can the pre-colonial history of Nigeria be reconstructed?

a. List any three articles of trade exported to  North Africa from Western Sudan during the trans-Saharan trade.
b. Highlight any four factors that contributed to the  decline of the trans-Saharan trade.

Explain any five features of the economy of the Igala people in pre-colonial period.

Highlight any five negative effects of the  trans-Atlantic slave trade on Nigeria.

a. Mention  any three city states of the Niger  Delta that had trade links with the Europeans.
b. Highlight any four roles played by King Jaja of Opobo in the commercial  activities of the Niger Delta.