Answer
a. All rectangles are quadrilaterals.
Every rectangle is a quadrilateral.
b. There is a set that has 16 subsets.
At least one set has 16 subsets.
We can find a set that has 16 subsets.
Work Step by Step
Some ways to express the $\forall$ symbol are: for all, for every, for any, for each, for arbitrary, given any
Some ways to express the $\exists$ symbol are: there exists, there exist, there exists at least one, for some, for at least one, we can find a.