SOUTH Africa needs to urgently fix energy, transport and security challenges if it is to reverse souring investor sentiment, executives said as President Cyril Ramaphosa targets 2 trillion rands ($111 billion) in new investments over the next five years. Executives were speaking at the South African Investment Conference in Johannesburg, launched by Ramaphosa in 2018 as a way to boost economic activity that had been in decline for over a decade in Africa's most advanced but struggling economy. Mismanagement and corruption at state-owned companies, including power utility Eskom and freight logistics group Transnet, have had a knock-on effect on ports…