1 ene 1300 año - Abacus

Descripción:

The abacus was a calculating device also made by the Chinese. The Abacus consists of beads or disks that can be moved up and down on a series of sticks or strings within a usually wooden frame. Abacus isn't a self calculating device, it is simply just a tool to help. In general, its a tool to help with calculating.

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