Context and question: The analog information encoded on LaserDiscs does not include any form of built-in checksum or error correction. Because of this, slight dust and scratches on the disc surface can result in read-errors which cause various video quality problems: glitches, streaks, bursts of static, or momentary picture interruptions. In contrast, the digital MPEG-2 format information used on DVDs has built-in error correction which ensures that the signal from a damaged disc will remain identical to that from a perfect disc right up until the point at which damage to the disc surface is so substantial that it prevents the laser from being able to identify usable data.
What video problems on a LaserDisc can be caused by dust or scratches?
Answer: glitches, streaks, bursts of static, or momentary picture interruptions
Context and question: Surveys show that red is the color most associated with courage. In western countries red is a symbol of martyrs and sacrifice, particularly because of its association with blood. Beginning in the Middle Ages, the Pope and Cardinals of the Roman Catholic Church wore red to symbolize the blood of Christ and the Christian martyrs. The banner of the Christian soldiers in the First Crusade was a red cross on a white field, the St. George's Cross. According to Christian tradition, Saint George was a Roman soldier who was a member of the guards of the Emperor Diocletian, who refused to renounce his Christian faith and was martyred. The Saint George's Cross became the Flag of England in the 16th century, and now is part of the Union Flag of the United Kingdom, as well as the Flag of the Republic of Georgia.
Why is the color red worn in the Catholic Church?
Answer: unanswerable
Context and question: The evolutionary relationships and heredity of a group of organisms is called its phylogeny. Phylogenetic studies attempt to discover phylogenies. The basic approach is to use similarities based on shared inheritance to determine relationships. As an example, species of Pereskia are trees or bushes with prominent leaves. They do not obviously resemble a typical leafless cactus such as an Echinocactus. However, both Pereskia and Echinocactus have spines produced from areoles (highly specialised pad-like structures) suggesting that the two genera are indeed related.
What does the phylogeny of a group represent?
Answer:
relationships and heredity