Which sentence states a fact?

 - The sitting U.S. president's airplane, Air Force One, is the most important symbol of the American government.
 - It costs over two hundred thousand dollars per hour to fly Air Force One, the official airplane of the President of the United States.
The second sentence states a fact.
It costs over two hundred thousand dollars per hour to fly Air Force One, the official airplane of the President of the United States.
It can be proved by reading about Air Force One on the White House website.
The first sentence states an opinion.
The sitting U.S. president's airplane, Air Force One, is the most important symbol of the American government.
Most shows what a person believes, thinks, or feels. Another person might have a different opinion about which symbol of the American government is most important.