Problem: Wood:

Heartwood is often visually distinct from the living sapwood, and can be distinguished in a cross-section where the boundary will tend to follow the growth rings. For example, it is sometimes much darker. However, other processes such as decay or insect invasion can also discolor wood, even in woody plants that do not form heartwood, which may lead to confusion.

In what part of a tree's cross-section is heartwood visible?
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A: growth rings


Problem: Colloquially, the term university may be used to describe a phase in one's life: "When I was at university..." (in the United States and Ireland, college is often used instead: "When I was in college..."). In Australia, Canada, New Zealand, the United Kingdom, Nigeria, the Netherlands, Spain and the German-speaking countries university is often contracted to uni. In Ghana, New Zealand and in South Africa it is sometimes called "varsity" (although this has become uncommon in New Zealand in recent years). "Varsity" was also common usage in the UK in the 19th century.[citation needed] "Varsity" is still in common usage in Scotland.
Mexico refers to a university in what other way?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
According to the 2010 revison of the UN World Population Prospects, Guinea-Bissau's population was 1,515,000 in 2010, compared to 518,000 in 1950. The proportion of the population below the age of 15 in 2010 was 41.3%, 55.4% were aged between 15 and 65 years of age, while 3.3% were aged 65 years or older.
What was the population of Guinea-Bissau in 2010?
A: 1,515,000


Context and question: Fryderyk Chopin was born in Żelazowa Wola, 46 kilometres (29 miles) west of Warsaw, in what was then the Duchy of Warsaw, a Polish state established by Napoleon. The parish baptismal record gives his birthday as 22 February 1810, and cites his given names in the Latin form Fridericus Franciscus (in Polish, he was Fryderyk Franciszek). However, the composer and his family used the birthdate 1 March,[n 2] which is now generally accepted as the correct date.
On what date was Frédéric born on?
Answer: 22 February 1810


Question: The convention followed by many British publishers (including scientific publishers, like Nature, magazines, like The Economist and New Scientist, and newspapers, like The Guardian and The Times) and U.S. newspapers is to use sentence-style capitalisation in headlines, where capitalisation follows the same rules that apply for sentences. This convention is usually called sentence case. It may also be applied to publication titles, especially in bibliographic references and library catalogues. Examples of global publishers whose English-language house styles prescribe sentence-case titles and headings include the International Organization for Standardization.
Is there an answer to this question: Which popular global publisher utilizes sentence case for titles and headers?

Answer: International Organization for Standardization


Question: The single most important piece of Byzantine Christian mosaic art in the East is the Madaba Map, made between 542 and 570 as the floor of the church of Saint George at Madaba, Jordan. It was rediscovered in 1894. The Madaba Map is the oldest surviving cartographic depiction of the Holy Land. It depicts an area from Lebanon in the north to the Nile Delta in the south, and from the Mediterranean Sea in the west to the Eastern Desert. The largest and most detailed element of the topographic depiction is Jerusalem, at the center of the map. The map is enriched with many naturalistic features, like animals, fishing boats, bridges and palm trees
Is there an answer to this question: What is the most important mosaic piece built by Byzantine Christians?

Answer:
the Madaba Map