They recorded numbers using the knots on a string called a quipu.
Name is a form of identifier of a person and it's easier for our brains to remember "This was John" than "This was that tall guy with dark hair and blue eyes". The other reason is that it's usually kind to exchange names when one has a chat with someone else.
<em>Hello ~</em>
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My name is Irxdscent, and I will be answering your question today! :D
<h2>→ <u>Answer :-</u></h2>
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D. Quadrant IV.
<h2>→ <u>Explanation :-</u></h2>
<u />
The Cosine ratio is on the <u>reciprocal</u>, and <u>positive</u> of the forth quadrant.
Hope It Helps! ~
<em>~ Learn With Lrxdscent ~</em>
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ɪ ʀ x ᴅ ꜱ ᴄ ᴇ ɴ ᴛ
Both writers share personal anecdotes to develop their central ideas