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1_______. This system was first developed in India in the 3rd century BC. 2_______.
The important innovation in the Arabic system was the use of positional notation, in which individual number symbols assume different values according to their position in the written numeral. 3_______. The symbol 0 makes it possible to differentiate between 11, 101, and 1,001 without the use of additional symbols, and all numbers can be expressed in terms of ten symbols, the numerals from 1 to 9 plus 0. 4_______.