Question

What properties are shared by rectangles

Answer 1

--  opposite pairs of sides are equal
--  opposite pairs of sides are parallel
--  interior angles are right angles
--  sum of the interior angles is 360°
--  opposite angles are supplementary
--  adjacent angles are supplementary
--  all of them have at least 2 lines of symmetry (some have 4)

Answer 2

Right angles and 2 different sets of the same side 
lengths