Anna Werner reports on the new details.
The video shows one of the students dump a liquid from a plastic bag onto a crepe before presenting it to the panel of teachers.
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I've spoken to a couple of friends of Olivia's and I have spoken to the coroner's office and her death is a mystery.
In an August interview with photographer Dave Naz, Nova said that she was shaking with nerves the first time she stripped for a project.
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