4th July: US Independence Day

It's the fourth of July - so here are 10 things you might not know about America.

1. The smallest US state is Rhode Island with an area of 1,545 square miles (4,002 sq km). The largest state by area is Alaska with 663,268 square miles (1,717,854 sq km) - but not by population. Although Alaska is 429 times larger than Rhode Island, Rhode Island has a significantly larger population. Alaska has the longest coastline in the United States at 6,640 miles (10,686 km) - more than all of the other 49 states put together. It also has the eleven highest mountains in the US, including the highest, Mount McKinley, 20,236 ft (6168 m) high.
2. The highest peak in mainland USA is Mount Whitney in California, at 14,505 feet (4421m). 59th on the list is Mauna Kea in Hawaii at 13,796 ft (4205 m) - but Mauna Kea has the distinction that, if you measured it from the bottom of the ocean around Hawaii, rather than from sea level, it would be taller than Mount Everest.
3. Only one state does not have a straight line in its boundary - Hawaii. Hawaii is also the newest state, having been granted statehood in 1959.
4. The US flag must be one of the most recognisable in the world, and most people know that the stripes represent the original thirteen colonies and the stars represent the fifty states; but you may not know that there have been 27 official versions of the flag (with differing numbers of stars). The flag changes when new states are added - the new star being officially added on the 4th of July following the admission of the new state. The current version of the US flag is the longest lasting one - there haven't been any new states since Hawaii. The design for the configuration of the stars was designed by a 17 year old student, Robert G. Heft as a school project. His teacher wasn't impressed - she gave him a B-, but had to eat her words and bump his grade up to an A when his design was chosen.
5. The US has no official language, although the most commonly spoken language and the one used by government, is English.
6. There are hidden images in the one dollar bill. Many of these can be explained, possibly, by the human tendency to see patterns and images in things; but there are some things you might not have noticed. On the left side of the front face is a circle with a letter in it. The letter represents which Federal Reserve bank printed it. If there is a star after the serial number, it means that it is a "replacement note" and has the same number as another bill. The star is printed on so that no two bills have the same number. These notes are sought after by collectors so you might be able to sell it on ebay for rather more than one dollar! Look very carefully at the number one on the front and you can see a small creature beside it. Some people think it's an owl, others a Spider. The consensus is that it's a spider because it appears to be sitting in a web.
7. About 35 million Americans share DNA with at least one of the 102 pilgrims who arrived aboard the Mayflower in 1620.
8. Despite being known as "The Land of the Free," the USA has a higher percentage of its population in prison than any other country in the world.
9. Early drafts of the Declaration of Independence were written on paper made out of Hemp (cannabis), although the final document was printed on parchment.
10. There are three towns in the United States called “Santa Claus“, and a town in Michigan called “Hell“.

For money nerds, the places represented by the letters on the dollar bill (fact #6) are Boston – A, New York – B, Philadelphia – C, Cleveland – D, Richmond – E, Atlanta – F, Chicago – G, St. Louis – H, Minneapolis – I, Kansas City – J, Dallas – K, San Francisco – L.