One of the main reasons that the Three Gorges dam was built was to prevent flooding further downstream. The need for a dam was highlighted in 1954 when people were killed as a result of flooding of the Yangtze River.
Arab Spring refers to the democratic uprisings that arose independently and spread across the Arab world in 2011. The movement originated in Tunisia in December 2010 and quickly took hold in Egypt, Libya, Syria, Yemen, Bahrain, Saudi Arabia, and Jordan.
In October 1973 Arab nations slashed oil production in protest at American support for Israel during it's war against Egypt and Syria. Oil prices sky-rocketed. We hear from former deputy secretary general of OPEC, Dr Fadhil Chalabi, about the struggle for control of oil in the early 1970s. (Photo: An American car displays a 'No Gas' sign during the 1973-74 oil crisis).