D. The measure of how stretched out an ellipse is, is referred to as <u>eccentricity.</u>
<h3>What is eccentricity of ellipse?</h3>
Eccentricity for an ellipse is the ratio of the length of the semimajor axis (a) to the distance (c )between the ellipse's center and each focus.
e = c/a
The greatest ellipse has the smallest eccentricity, whereas the perfect circle has the maximum eccentricity. The eccentricity of an ellipse e, which ranges from 0 (the limiting case of a circle) to 1 (the length of the ellipse), is used to determine how long it is (the limiting case of infinite elongation, no longer an ellipse but a parabola). Because the distance from the fixed point on the plane has a constant ratio that is less than the distance from the fixed line on the plane, the eccentricity of an ellipse ranges from 0 to 1.
Learn more about eccentricity here:
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