(a.k.a. Subs) (includes all types, all classes) (2015 figures)
The United States Navy maintains a fleet of 72 active submarines. A typical submarine goes to sea with a crew of about 140.

(Moden layout; A₀ to C₇)
Most modern keyboards have 88 keys, comprising seven octaves and an additional major third. A full-size, acoustic piano may have as many as 12,000 separate parts.

(2016 figures) (sovereign states recognized by the UN only)
The continent of Africa includes 54 sovereign countries recognized by the United Nations as of 2016. It is the second-most populous continent in the world, with 1.1 billion inhabitants.

(a.k.a. Henihco'oo; a.k.a. Héetíhco'oo) (December 2014 figures; Wyoming Park area)
As of the 2014 population count, there were 104 wolves living in Yellowstone National Park, in twelve packs. All of the wolves now living in the Park are thought to have descended from the 66 wolves (re)introduced into the Park in 1995-96.

(Carcharodon carcharias) (average; including developing rows)
A Great White Shark has 48 exposed teeth on their upper and lower jaws. Behind these exposed teeth are developing teeth — up to 300 in about 5 rows. The sharks will continuously lose and replace the exposed teeth throughout their lives.

(a.k.a. Periodic Table of the Elements, a.k.a chemical elements) (confirmed elements as of 2016)
From element number one, hydrogen, to element one-hundred eighteen, ununoctium, there are 118 confirmed elements on the Periodic Table. Ninety-four of the elements exist in nature, and the remaining twenty-four have only been synthesized in labs (not having occurred naturally in the time since scientists have begun researching them)

(a.k.a. Union Terminal; a.k.a. Joint Station; a.k.a. Union Depot) (2016 figures)
Typically shared between multiple railroad companies and stations, there are about 135 "Union Stations" in the United States. Of these, the busiest station is Chicago Union Station, which handles 120,000 passengers each year.