Extract the answer to the question from the following context. Question: Why do so many people have so much variation in their family history? Context: One problem with these assignments is admixture. Many people have a highly varied ancestry. For example, in the United States, colonial and early federal history were periods of numerous interracial relationships, both outside and inside slavery. This has resulted in a majority of people who identify as African American having some European ancestors. Similarly, many people who identify as white have some African ancestors. In a survey in a northeastern U.S. university of college students who identified as "white", about 30% were estimated to have up to 10% African ancestry.
Ans: colonial and early federal history were periods of numerous interracial relationships

Extract the answer to the question from the following context. Question: Glass with high density materials are sometimes called? Context: Glass has the ability to refract, reflect, and transmit light following geometrical optics, without scattering it. It is used in the manufacture of lenses and windows. Common glass has a refraction index around 1.5. This may be modified by adding low-density materials such as boron, which lowers the index of refraction (see crown glass), or increased (to as much as 1.8) with high-density materials such as (classically) lead oxide (see flint glass and lead glass), or in modern uses, less toxic oxides of zirconium, titanium, or barium. These high-index glasses (inaccurately known as "crystal" when used in glass vessels) cause more chromatic dispersion of light, and are prized for their diamond-like optical properties.
Ans: crystal

Extract the answer to the question from the following context. Question: Samurai follow what which focuses on interpersonal interactions? Context: The philosophies of Buddhism and Zen, and to a lesser extent Confucianism and Shinto, influenced the samurai culture. Zen meditation became an important teaching due to it offering a process to calm one's mind. The Buddhist concept of reincarnation and rebirth led samurai to abandon torture and needless killing, while some samurai even gave up violence altogether and became Buddhist monks after realizing how fruitless their killings were. Some were killed as they came to terms with these realizations in the battlefield. The most defining role that Confucianism played in samurai philosophy was to stress the importance of the lord-retainer relationship—the loyalty that a samurai was required to show his lord.
Ans: Confucianism

Extract the answer to the question from the following context. Question: Name a characteristic of All Quiet on the Western Front? Context: "Junior" Laemmle persuaded his father to bring Universal up to date. He bought and built theaters, converted the studio to sound production, and made several forays into high-quality production. His early efforts included the critically mauled part-talkie version of Edna Ferber's novel Show Boat (1929), the lavish musical Broadway (1929) which included Technicolor sequences; and the first all-color musical feature (for Universal), King of Jazz (1930). The more serious All Quiet on the Western Front (1930), won its year's Best Picture Oscar.
Ans: serious