What river is the weapons manufacturer that developed the M15 pistol located on?
Mississippi River
Title: Rock Island Arsenal
Passage: The Rock Island Arsenal comprises 946 acres , located on Arsenal Island, originally known as Rock Island, on the Mississippi River between the cities of Davenport, Iowa, and Rock Island, Illinois.  It lies within the state of Illinois.  It is home of First Army headquarters.  The island was originally established as a government site in 1816, with the building of Fort Armstrong.  It is now the largest government-owned weapons manufacturing arsenal in the United States.  It has manufactured military equipment and ordnance since the 1880s.  In 1919–1920 one hundred of the Anglo-American or Liberty Mark VIII tanks were manufactured, although too late for World War I.  It is designated as a National Historic Landmark.
Title: Python (missile)
Passage: The Rafael Python is a family of air-to-air missiles (AAMs) built by the Israeli weapons manufacturer Rafael Advanced Defense Systems, formerly RAFAEL Armament Development Authority.  Originally starting with the "Shafrir" (Hebrew: שפריר‎ ‎ , loosely translated as Dragonfly, a male form of inflection for Damselfly (שפרירית)) series, the "Shafrir-1" missile was developed in 1959, followed by the "Shafrir-2" in early 1970s.  Subsequently, the missiles were given the western name of ""Python"" by the parent company for export purposes, starting with the "Python-3" in 1978.  Since then, it has been further developed and evolved into the "Python-4", "Python-5", "Derby" and also, the SPYDER, an advanced ground-based air-defence system.  Currently, the missiles are in service with the armed forces of over fifteen countries from around the world.
Title: M15 pistol
Passage: The M15 General Officers is a .45 ACP pistol developed by the U.S. Army's Rock Island Arsenal from stock M1911 pistols as a replacement for the aging Colt Model 1903 and Model 1908 Pocket Hammerless pistols.  The pistol was issued to United States Army general officers as a personal weapon.
M15 pistol Rock Island Arsenal