Question

17. (a) Name the most effective tactual resource used for visually challenged
persons. Who developed this system ?
(b) List its two important features,
1​

Answer 1

Answer:

a,The most popular resource for visually challenged persons is Braille. Louis Braille developed this system and published it in 1821.braille is a system that uses combinations of raised dots to spell letters and numbers. braille system helps to the visually challenged persons through braille script consisting of raised dots that allow blind person to read and write.

b,These dot positions form a rectangle composed of 2 columns with 3 dots in each column. A single dot or any combination of dots may be raised at any of the 6 positions. Counting spaces, in which no dots appear, there are 64 English braille combinations in total.

Explanation:

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