We know that the diagonals of a rhombus always bisect each other at 90º. Let us assume that these are intersecting each other at point O in this rhombus.
Hence, EO = OD = 3.25 cm
A rough sketch of this rhombus can be drawn as follows.
(1) Draw a line segment BN of 5.6 cm and also draw its perpendicular bisector. Let it intersect the line segment BN at point O.
(2) Taking O as centre, draw arcs of 3.25 cm radius to intersect the perpendicular bisector at point D and E.
(3) Join points D and E to points B and N.
BEND is the required quadrilateral.