Question: An analog board was used in which third model of the Macintosh line?

Context paragraphs:
Power Mac G4: The Power Mac G4 is a series of personal computers designed, manufactured, and sold by Apple Computer, Inc. from 1999 to 2004 as part of the Power Macintosh line.  Built around the PowerPC G4 series of microprocessors, the Power Mac G4 was marketed by Apple as the first "personal supercomputers", reaching speeds of 4 to 20 gigaFLOPS.  This was the first existing Macintosh product to be officially shortened as "Mac", and is the last Mac able to boot into classic Mac OS.

List of mergers and acquisitions by Apple: Apple Inc. is an American multinational corporation that designs and manufactures consumer electronics and software products.  It was established in Cupertino, California, on April 1, 1976, by Steve Jobs, Steve Wozniak, and Ronald Wayne, and was incorporated on January 3, 1977.  The company's hardware products include the Macintosh line of personal computers, the iPod line of portable media players, the iPad line of tablets, the iPhone line of smartphones, the Apple TV line of digital media players, and the Apple Watch line of smartwatches.  Apple's software products include the OS X operating system, the iOS mobile operating system, the tvOS operating system, the watchOS operating system, the iTunes media browser, and the iLife suite of multimedia and creativity software.  As of 2017 , Apple is publicly known to have acquired 70 companies.  The actual number of acquisitions is possibly larger as Apple does not reveal the majority of its acquisitions unless discovered by journals.  Apple has also purchased stakes in two companies, as well as made two divestments. Apple has not released the financial details for the majority of its mergers and acquisitions.

Welcome to Macintosh (film): Welcome to Macintosh is a 2008 documentary film focusing on computer company Apple Inc. and its Macintosh line of computers.  The title comes from the original welcome message shown during the start-up of Macintosh computers.

Macintosh II series: The Macintosh II is a series of personal computers in Apple's Macintosh line.  The series debuted with the Macintosh II in 1987 and the final model was the Macintosh IIvx released in 1992.  The Centris and Quadra series of computers replaced the Macintosh II.

A/UX: A/UX is a discontinued Apple Computer implementation of the Unix operating system for some of its Macintosh computers.  It was Apple's first attempt at developing and marketing a Unix-based operating system to run on its Macintosh line.  A/UX requires a 68k-based Macintosh with an FPU and a paged memory management unit (PMMU), and various versions run on the Macintosh II, SE/30, Quadra and Centris series of machines.  A/UX was first released in 1988, with the final version of 3.1.1 released in 1995.  It is not related to Apple's current Unix branded macOS.

Power Macintosh 6100: The Power Macintosh 6100 is a personal computer designed, manufactured and sold by Apple Computer from March 1994 to March 1996 as part of the Power Macintosh line.  It is first computer to use the new PowerPC processor created by IBM and Motorola.  The low-profile ("pizza box") case was inherited from the Centris/Quadra 610 and 660AV models, and replaced the Macintosh Quadra series that used the Motorola 68040 processor, Apple's previous high end workstation line.  It was the earliest Macintosh model able to run Mac OS 9.

Power Macintosh 7100: The Power Macintosh 7100 is a personal computer that was designed, manufactured and sold by Apple Computer Inc. from March 1994 to January 1996.  It is the mid-range machine of the first generation of Power Macintosh line, between the Power Macintosh 6100 and the Power Macintosh 8100.  The 7100 re-used the Macintosh IIvx case with few changes.  There were two versions of the 7100; the original 66 MHz version and an 80 MHz version that replaced it in January 1995.

Power Macintosh 9500: The Power Macintosh 9500 (sold as Power Macintosh 9515 in Europe and Asia) is a personal computer designed, manufactured and sold by Apple Computer as part of the Power Macintosh line from May 1995 until February 1997.  It is powered by a PowerPC 604 processor, a second-generation PowerPC chip which was faster than the PowerPC 601 chip used in the Power Macintosh 8100.  The 180MP and 200 MHz models, introduced August 1996, use the enhanced PowerPC 604e processor.

Analog board: An analog board is a circuit board that contains the majority of analog circuitry in certain Apple Macintosh computers.  The analog board was one of two circuit boards within many early Macintosh computers, including the Macintosh 128K/512K/Plus, Macintosh SE series, and Macintosh Classic series.  The analog board contained several capacitors, a battery compartment, and some other analog circuitry.  Some later all-in-one Macintosh computers also included analog boards, with the most recent being the iMac G3 and eMac.  In these computers, the analog board functioned as the power supply to other parts within the system, and also functioned to control the CRT display within the computer.  The other board was the logic board, which contained all of the computer's digital logic circuitry, such as the processor and memory.

Macintosh Plus: The Macintosh Plus computer is the third model in the Macintosh line, introduced on January 16, 1986, two years after the original Macintosh and a little more than a year after the Macintosh 512K, with a price tag of US$2599.  As an evolutionary improvement over the 512K, it shipped with 1 MB of RAM standard, expandable to 4 MB, and an external SCSI peripheral bus, among smaller improvements.  It originally had the same generally beige-colored case as the original Macintosh ("Pantone 453"), but in 1987, the case color was changed to the long-lived, warm gray "Platinum" color.  It is the earliest Macintosh model able to run System 7 OS.

Supporting paragraphs: Analog board Macintosh Plus
Answer: Macintosh Plus