Translate the given Spanish text to English

Q: An expandable pulley (100).

A: Una polea expansible (100).
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Q: The second arm portion is pivotably connected to the walls.

A: La segunda porción del brazo se conecta en pivote a las paredes.
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Q: With this invention more exact descriptions can be obtained than the ones currently obtained with corneal topography device based in the Placido rings, being a simple system of easy implementation in a medical clinic.

A:
Este nuevo topografo corneal, al igual que el topografo corneal basado en los anillos de Placido, es un sistema simple de facil implementacion en un consultorio medico.
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