Which types of quadrilaterals have four congruent sides?
a) parallelogram and square
b) rectangle and rhombus
c) rhombus and square
d) rectangle and square

 The quadrilaterals have four congruent sides are C. ) rhombus and square. square has perpendicular angles inside the polygon while rhombus does not have, just opposite angles that are supplementary to each other. rectangles and parallelograms have different lengths and widths

Yes you are right the correct answer is b

21/2 or 5/2