Question 1121022
.
<pre>
According to the condition, the ellipse (or semi-ellipse)  semi-minor and semi-major axes are 5 m and 16/2 = 8 m, respectively.


Hence, the linear eccentricity is  {{{sqrt(8^2-5^2)}}} = 6.245 m.


It is the distance from the center of the semi-ellipse to its focuses.



<U>Answer</U>.  The two friends should stay at the focuses of the ellipse that are located at the distance of 6.245 m from the center of the ellipse.
</pre>

P.S.  &nbsp;&nbsp;To be exactly precise, &nbsp;the two friends should &nbsp;<U>LIE</U>&nbsp; on the floor at that locations to have their mouths and their ears 

maximally close to the focuses :-).


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For relevant lessons, &nbsp;see

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Quadratic-relations-and-conic-sections/Ellipse-definition--canonical-equation--characteristic-points-and-elements.lesson>Ellipse definition, canonical equation, characteristic points and elements</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Quadratic-relations-and-conic-sections/Ellipse-focal-property.lesson>Ellipse focal property</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Quadratic-relations-and-conic-sections/Tangen-lines-to-a-circle.lesson>Tangent lines and normal vectors to a circle</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Quadratic-relations-and-conic-sections/Tangent-lines-to-an-ellipse.lesson>Tangent lines and normal vectors to an ellipse</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Quadratic-relations-and-conic-sections/Optical-property-of-an-ellipse.lesson>Optical property of an ellipse</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Quadratic-relations-and-conic-sections/Optical-property-of-an-ellipse-revisited.lesson>Optical property of an ellipse revisited</A> 


&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/Quadratic-relations-and-conic-sections/Practical-problems-from-the-archive-related-to-ellipses-and-parabolas.lesson>Practical problems from the archive related to ellipses and parabolas</A> 



Also, &nbsp;you have this free of charge online textbook in ALGEBRA-II in this site

&nbsp;&nbsp;&nbsp;&nbsp;<A HREF=https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson>ALGEBRA-II - YOUR ONLINE TEXTBOOK</A>.


The referred lessons are the part of this online textbook under the topic 
"<U>Conic sections: Ellipses. Definition, major elements and properties. Solved problems</U>".



Save the link to this textbook together with its description


Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson


into your archive and use when it is needed.


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<U>Comment from student</U> : &nbsp;&nbsp;Thank you so much maam. &nbsp;How about the letter &nbsp;B? 



<U>My response</U> :  &nbsp;&nbsp;I answered both questions.  &nbsp;Read my answer attentively . . .