Step through the construction below. Each time a new point is inserted, watch the tree decide whether it needs to split a region:
Testing of a £50m ultrasound system designed to stop fish being sucked into the cooling pipes of Britain's new nuclear power station has gone "really well".
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Kevin Church/BBC News
The workers described being threatened and beaten, having their passports withheld, and being forced to work long hours in unsanitary conditions.
Трамп высказался о непростом решении по Ирану09:14