One diagonal of a parallelogram is 50 cm, and the perpendicular distance from any opposite vertex to this diagonal is 25 cm. Find the total area of the parallelogram (in cm2).

In a quadrilateral IJKL, ∠I = 36° and ∠J = 44°. The internal angle bisectors of ∠K and ∠L intersect at a point Z. What is the measure of ∠LZK?

Which of the following options is NOT a necessary characteristic of a kite?

ABCD is a quadrilateral in which AB || DC, and E and F are the mid-points of the diagonals AC and BD, respectively. If AB = 30 cm, BC = 20 cm, DC = 86 cm, and AD = 84 cm, then what is the length (in cm) of EF?