Obama leaves South Africa for Tanzania

ROUGH CUT - NO REPORTER NARRATION<br/> <br />U.S. President Barack Obama on Monday (July 1) left Cape Town aboard presidential jet Air Force One, bound for Tanzania.<br/> <br />Obama was in South Africa on the second leg of a three-nation Africa trip including Senegal, South Africa and Tanzania.<br/> <br />The U.S. leader and his family visited the bleak former prison of Robben Island to pay tribute to ex-inmate and former president Nelson Mandela, now critically ill in hospital.<br/> <br />The president, the first African-American U.S. head of state, said Mandela's struggle against apartheid paved the way for freedom and opportunity well beyond South Africa's borders.<br/> <br />In Cape Town, the president announced a $7 billion U.S. initiative to double access to electric power on a continent where only one in three people have electricity.<br/> <br />This would include the renewal of an agreement to cut tariffs on African exports to the United States.<br/> <br />While in Cape Town, Obama also visited a health centre