premise: River Raid is a scrolling shooter video game designed and developed by Carol Shaw, and published by Activision in 1982 for the Atari 2600 video game console. Over a million game cartridges were sold. Activision later ported the title to the Atari 5200, ColecoVision, and Intellivision game consoles, as well as to the Commodore 64, IBM PCjr, MSX, ZX Spectrum, and Atari 8-bit family home computers.
hypothesis: Over one million, but less than 3 million cartridges of River Raid were sold.
reason: Neither because we know over a million copies were sold, but we don't know exactly how many were sold given the information.