Let's make the convertion from acre to squared ft:
[tex]435\text{ acre(}\frac{43560\text{ sq ft}}{1\text{ acre}})=18948600\text{ sq ft}[/tex]Now, lets convert this to squared miles:
[tex]18948600\text{ sq ft(}\frac{1\text{ mi}}{5280\text{ ft}})\text{(}\frac{1\text{ mi}}{5280\text{ ft}})=0.6796875[/tex]Therefore 435 acres is 0.6796875 squared miles.
