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.
Mutasaâs strategic acquisitions strategy propelled him from mere commodity broker to one of the countryâs richest men. Hoe now owns TA Holdings, a diversified group listed on the Zimbabwe Stock Exchange, and BPâs refined oil marketing assets in Zimbabwe.