America's Cup Ep3: The Boats - What are they, how do they work, what are the three types?

It’s easy to see why the 37th America’s Cup is widely considered to be the most technically complex Cup cycle. With some teams choosing to produce three different boats, the LEQ12, the AC40 and the AC75, running a modern campaign is a demanding logistical and technical challenge.
So what are the boats and what role do they play on the road to the America’s Cup?
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