Smithton City Hall, the Ace Supermarket, and the Smithton post office all are on Main Street. The supermarket is 3.25 kilometers north of City Hall. The post office is 1.75 kilometers south of City Hall. How far apart are Ace Supermarket and the Smithton post office? A. 1.5 kilometers B. 2.5 kilometers C. 5 kilometers D. 6 kilometers