Decide if the following statements are true or false. If a statement is false, provide a diagram of a counterexample.

1. All squares are rectangles.

   Answer (a):

   True.

2. All quadrilaterals are parallelograms.

   Hint (b):

   Can you draw a quadrilateral without parallel sides?

3. All squares are rhombi.

   Answer (c):

   True.