This is the relevant information: The ferry's single route runs 5.2 miles (8.4 km) through New York Harbor between the New York City boroughs of Manhattan and Staten Island, with ferry boats making the trip in approximately 25 minutes.
This justifies what answer for what question? Q & A:
Passage: The Staten Island Ferry is a passenger ferry route operated by the New York City Department of Transportation. The ferry's single route runs 5.2 miles (8.4 km) through New York Harbor between the New York City boroughs of Manhattan and Staten Island, with ferry boats making the trip in approximately 25 minutes. The ferry operates 24 hours a day, 7 days a week, with boats leaving every 15 to 20 minutes during peak hours and every 30 minutes at other times. It is the only direct mass-transit connection between the two boroughs. Historically, the Staten Island Ferry has charged a relatively low fare compared to other modes of transit in the area; and since 1997, the route has been fare-free. The Staten Island Ferry is one of several ferry systems in the New York City area, and is operated separately from other systems such as NYC Ferry and NY Waterway.

Question: Based on this passage, how far is it from staten island to manhattan?
5.2 miles ( 8.4 km )