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Today's episode is sponsored by Smart Travel, a podcast from NerdWallet.
Do you have a friend who treats airfare like a puzzle and somehow always ends up with a first class upgrade?
Smart Travel is like that friend, minus the group texts.
NerdWallet's travel journalists break down the pros and cons of travel decisions,
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Welcome to the documentary from the BBC World Service.
This is The Fifth Floor, at the heart of global storytelling with BBC journalists from all around the world.
I'm your host, Faranak Amidi.
Last week, the American government charged the former Cuban leader Raul Castro with conspiracy to kill U.S. nationals.
They accused him of playing a part in the downing of two planes in 1996, which were flying between Cuba and Florida.
This comes after months of the U.S. putting increasing pressure on the country.
In January, President Trump threatened to impose tariffs on any country who supplied oil to the island,
resulting in huge energy shortages ever since, with some parts of the country being without power for 22 hours a day.