There may be no single cause of bipolar disorder (aka manic depression). Instead, research indicates the causes of bipolar disorder are probably a combination of biochemical, genetic and environmental factors that may trigger and perpetuate the chemical imbalances in the brain.
Net worth: $829 million. Telecommunications mogul Strive Masiyiwa is widely regarded as the richest man in Zimbabwe and is one of the richest men in Africa with a net worth of more than US$800 million.
Meet Africa's richest man: Aliko Dangote. Forbes magazine estimates his wealth at $25bn, making him the 23rd richest man in the world with a growing portfolio of investments across Africa.eet Africa's richest man: Aliko Dangote. Forbes magazine estimates his wealth at $25bn, making him the 23rd richest man in the world with a growing portfolio of investments across Africa.