Extract the answer to the question from the following context. Question: Plants are eaten by? Context: The elimination of wolves from Yellowstone National Park had profound impacts on the trophic pyramid. Without predation, herbivores began to over-graze many woody browse species, affecting the area's plant populations. In addition, wolves often kept animals from grazing in riparian areas, which protected beavers from having their food sources encroached upon. The removal of wolves had a direct effect on beaver populations, as their habitat became territory for grazing. Furthermore, predation keeps hydrological features such as creeks and streams in normal working order. Increased browsing on willows and conifers along Blacktail Creek due to a lack of predation caused channel incision because they helped slow the water down and hold the soil in place.
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Answer: herbivores

Extract the answer to the question from the following context. Question: Of the three founding celebrity investors of Planet Hollywood whose full names are mentioned, which has a first and last name that begin with the same letter? Context: Schwarzenegger was a founding celebrity investor in the Planet Hollywood chain of international theme restaurants (modeled after the Hard Rock Cafe) along with Bruce Willis, Sylvester Stallone and Demi Moore. Schwarzenegger severed his financial ties with the business in early 2000. Schwarzenegger said the company had not had the success he had hoped for, claiming he wanted to focus his attention on "new US global business ventures" and his movie career.
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Answer: Sylvester Stallone

Extract the answer to the question from the following context. Question: How is samadhi trained? Context: In the language of the Noble Eightfold Path, samyaksamadhi is "right concentration". The primary means of cultivating samadhi is meditation. Upon development of samadhi, one's mind becomes purified of defilement, calm, tranquil, and luminous.
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Answer:
meditation