Question

a perfectly elastic price-demand curve is parallel to the X-axis. why or why-not?

Answer 1

Perfectly elastic demand means that consumers are extremely responsive to changes in price. If a seller increased price even a little bit, consumers will shift to buying the same product from a different producer or shift to its substitutes. A product with perfectly elastic demand has perfect substitutes. Thus, the producer has no choice but to charge the same price regardless of the demand.
That is why, the curve is parallel to X-axis.

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Answer 2

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