In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Q: He stepped down as president of his country in 1985, but continued as head of the ruling party until 1990. His government emphasized a form of rural socialism known as ujamaa, and, in 1978, troops under his leadership entered Uganda, deposing Idi Amin. After his retirement he remained active in African politics, and was known throughout the continent as Mwalimu, Swahili for teacher. FTP, identify this first president of Tanzania, who died in October, 1999.

A: History
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Q: These compounds are described using the E-Z [E dash Z] notation when they occur across alkenes, and a more generalized version of that notation is the cis-trans notation. Both of those are examples of diastereomers [di-uh-stereo-mers], and examples of these include cyclohexane and hexene. Differing bonding patterns make up structural ones of these compounds. When these compounds are mirror images of each other, they are referred to as enantiomers [en-anti-omers]. For 10 points, name these compounds that have varying chemical structures despite having the same chemical formula.

A: Science
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Q: During glycogen synthesis, a diphosphate derivative of this molecule serves as a carrier for glucose monomers. Cytosine spontaneously deaminates to form this molecule, which can be specifically removed by DNA glycosidase. Marshall Nirenberg showed that a polymer of this molecule, added to a certain cell-free extract, would result in the creation of proteins with radioactive phenylalanine. A "pseudo-" form of this molecule, symbolized psi, is found in one arm of transfer RNA, and it forms two hydrogen bonds with adenine. For 10 points, name this nucleotide that replacing thymine in RNA.

A:
Science
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