She should have choose a circular shaped item, so that she can make a cilcle.
Try to recall the properties of rectangle.
Think about the polygon with 4 sides
The radius of the circle will be equal to the length of the rope.
Think of name of line segment between opposite vertices of rectangle
Circle with a proper circular shape will be a perfect circle.
Adjacent sides have common vertex.
Use radius to find the bigger circle.
Shape of a circle
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