Were BBC Master and Acorn Archimedes both sold by Acorn Computers?
yes
BBC Master
The BBC Master is a home computer released by Acorn Computers in early 1986.
 It was designed and built for the British Broadcasting Corporation (BBC) and was the successor to the BBC Micro Model B.
 The Master 128 remained in production until 1993.
Acorn Archimedes
The Acorn Archimedes is a family of personal computers designed by Acorn Computers Ltd in Cambridge, England and sold in the late-1980s to mid-1990s, their first general purpose home computer based on their own ARM architecture (then the CPU and architecture was known as Acorn RISC Machine, or ARM, that later became one of the most widely used CPU architectures in the world, e.g. used in most smartphones).
 The first Archimedes was launched in 1987.
Acornsoft
Acornsoft was the software arm of Acorn Computers, and a major publisher of software for the BBC Micro and Acorn Electron.
 As well as games, it also produced a large number of educational titles, extra computer languages and business and utility packages – these included word processor "VIEW" and the spreadsheet "ViewSheet" supplied on ROM and cartridge for the BBC Micro/Acorn Electron and included as standard in the BBC Master and Acorn Business Computer. Acorn A7000
The A7000 and A7000+ were Acorn Computers' entry level computers based on the RiscPC architecture.
 Launched in 1995, they replaced some of the models of the Acorn Archimedes range.
 After the breakup of Acorn Computers in 1998, Castle Technology bought the rights to continue production of the A7000+.
 The A7000 used the ARM7500 system on chip which combined the separate ARM CPU, MMU, VIDC20 video chip and IOMD IO controller of the RiscPC into a single chip. Acorn Computers
Acorn Computers Ltd. was a British computer company established in Cambridge, England, in 1978.
 The company produced a number of computers which were especially popular in the UK, including the Acorn Electron and the Acorn Archimedes.
 Acorn's BBC Micro computer dominated the UK educational computer market during the 1980s.
 It is more known for its BBC Micro model B computer than for its other products. Zarch
Zarch (also known under its ported name of Virus) is a computer game developed by David Braben (better known as the co-author of "Elite") in 1987 , for the release of the Acorn Archimedes computer.
 "Zarch" started off as a demo called "Lander" which was bundled with almost all releases of the Acorn Archimedes. Acorn User
Acorn User magazine was founded by Acorn Computers in 1982, contract-published by Addison-Wesley, to coincide with the launch of the BBC Micro.
 It covered the range of Acorn home computers, the BBC Micro and Atom at first and later the Electron, Archimedes and Risc PC. RiscPC
The RiscPC (stylised with a half-space as Risc PC , also referred to as Risc PC and codenamed Medusa) was Acorn Computers's next generation RISC OS/Acorn RISC Machine computer, launched on 15 April 1994, which superseded the Acorn Archimedes.
 The "Acorn PC card" and software allows PC compatible software to be run. The Micro User
The Micro User (titled BBC Micro User in the first three issues) was a British specialist magazine catering to users of the BBC Microcomputer series, Acorn Electron, Acorn Archimedes and, to a limited extent, the Cambridge Z88.
 It had a comprehensive mix of reviews of games, application software, and the latest Acorn computers; type-in programs (duplicated on a "cover disk" which was available separately), a correspondence page offering help with computer problems, and approachable technical articles on programming and the BBC Micro's internals. ARX (operating system)
ARX was an unreleased Mach-like operating system written in Modula-2+ developed by Acorn Computers Ltd in the Acorn Research Centre (ARC) UK and later Olivetti Research Center and later on Software Technology Laboratory (when Olivetti bought out Acorn) at Palo Alto for their new ARM RISC processors based Archimedes computers range.
 According to the project Application Manager during the project, while Acorn was developing the kernel, it used C and Acorn Modula Execution Library (CAMEL) in Acorn Extended Modula-2 (AEM2) compiler (ported from Modula-2 ETH using Econet hardware), though never released externally, CAMEL was ported to use it in SUN Unix machines, in an effort to port Sun's workstations Sun NeWS to the Archimedes, and after Olivetti bought out Acorn, developed a compiler based on AEM2 for the Modula-3 programming Language.