In the mid to late 1990s many higher-end AV receivers included the demodulator circuit specifically for the LaserDisc players RF modulated Dolby Digital AC-3 signal. By the late 1990s with LaserDisc players and disc sales declining due to DVD's growing popularity the AV receiver manufacturers removed the demodulator circuit. Although DVD players were capable of playing Dolby Digital tracks, the signal out of DVD player were not in a modulated form and not compatible with the inputs designed for LaserDisc AC-3. Outboard demodulators were available for a period that convert the AC-3 signal to standard Dolby Digital signal that was compatible with the standard Dolby Digital/PCM inputs on capable AV receivers. Another type marketed by Onkyo and others converted the RF AC-3 signal to 6-channel analog audio.
What competition caused LaserDisc sales to decline?
DVD's growing popularity

Americans with Sub-Saharan African ancestry for historical reasons: slavery, partus sequitur ventrem, one-eighth law, the one-drop rule of 20th-century legislation, have frequently been classified as black (historically) or African American, even if they have significant European American or Native American ancestry. As slavery became a racial caste, those who were enslaved and others of any African ancestry were classified by what is termed "hypodescent" according to the lower status ethnic group. Many of majority European ancestry and appearance "married white" and assimilated into white society for its social and economic advantages, such as generations of families identified as Melungeons, now generally classified as white but demonstrated genetically to be of European and sub-Saharan African ancestry.
What were those with Sub-Saharan African ancestory classified as?
black (historically) or African American

On October 28, 1989, the Ukrainian Supreme Soviet decreed that effective January 1, 1990, Ukrainian would be the official language of Ukraine, while Russian would be used for communication between ethnic groups. On the same day The Congregation of the Church of the Transfiguration in Lviv left the Russian Orthodox Church and proclaimed itself the Ukrainian Greek Catholic Church. The following day, thousands attended a memorial service at Demianiv Laz, and a temporary marker was placed to indicate that a monument to the "victims of the repressions of 19391941" soon would be erected.
For what reason would the Russian be spoken?
communication between ethnic groups