Area of Parallelograms

1. The parallelogram shown below has an area of 40 units $^{2}$.

Find the missing base.

$b=$ _______ units

2. The parallelogram shown below has an area of 28 units $^{2}$.

Find the missing base.

$b=$ _______ units

3. The parallelogram shown below has an area of 21 units $^{2}$.

Find the missing height.

$h=$ _______ units

4. The parallelogram shown below has an area of 135 units $^{2}$.

Find the missing base.

$b=$ _______ units