Which statement best defines an ellipse and contrasts it with a circle?

Starting with the circle $x^2+y^2=r^2$, which algebraic substitution describes stretching the circle horizontally by factor $s>1$ to form an ellipse?

Find the foci coordinates for the ellipse $9x^2+16y^2=144$ (ellipse centered at origin).

Is the point ($3$, $2$) inside, on, or outside the ellipse $\frac{x^2}{16}+\frac{y^2}{9}=1$?

Design an elliptical garden with major axis length $20$ and minor axis length $12$, centered at the origin with horizontal major axis. Provide the standard-form equation and the distance from the center to each focus.