[Isosceles, Inscribed, and Circumscribed Trapezoids] [Varignon's Parallelogram

Find the angles and sides of the quadrilateral with vertices at the midpoints of the sides of an isosceles trapezoid, whose diagonals are equal to 10 and intersect at an angle of $40^{\circ}$.

#
The quadrilateral with vertices at the midpoints of the sides of a given trapezoid is a rhombus.

## Answer

$40^{\circ}, 140^{\circ}, 40^{\circ}, 140^{\circ} ; 5,5,5,5$.