All rhombuses have the following in common:
4 sides
All sides have the same length
Opposite angles are congruent (not necessarily right angles)
Diagonals bisect each other at right angles
Therefore, the correct answers are:
4 sides
the same length
all sides
4 right angles (This is incorrect since a rhombus does not necessarily have four right angles. A rhombus with four right angles is a square.)
~~~Harsha~~~