Problem: Glass:

Fused quartz is a glass made from chemically-pure SiO2 (silica). It has excellent thermal shock characteristics, being able to survive immersion in water while red hot. However, its high melting-temperature (1723 C) and viscosity make it difficult to work with. Normally, other substances are added to simplify processing. One is sodium carbonate (Na2CO3, "soda"), which lowers the glass transition temperature. The soda makes the glass water-soluble, which is usually undesirable, so lime (calcium oxide [CaO], generally obtained from limestone), some magnesium oxide (MgO) and aluminium oxide (Al2O3) are added to provide for a better chemical durability. The resulting glass contains about 70 to 74% silica by weight and is called a soda-lime glass. Soda-lime glasses account for about 90% of manufactured glass.

Why is lime often added to glass?
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A: better chemical durability

Problem: Baptists are individuals who comprise a group of Christian denominations and churches that subscribe to a doctrine that baptism should be performed only for professing believers (believer's baptism, as opposed to infant baptism), and that it must be done by complete immersion (as opposed to affusion or sprinkling). Other tenets of Baptist churches include soul competency (liberty), salvation through faith alone, Scripture alone as the rule of faith and practice, and the autonomy of the local congregation. Baptists recognize two ministerial offices, elders and deacons. Baptist churches are widely considered to be Protestant churches, though some Baptists disavow this identity.
What two ministerial offices do Baptists no longer recognize?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Sanskrit (/snskrt/; Sanskrit: samskrtam [smskrtm] or samskrta, originally samskrta vak, "refined speech") is the primary sacred language of Hinduism, a philosophical language in Buddhism, Hinduism, Sikhism and Jainism, and a literary language that was in use as a lingua franca in Greater India. It is a standardised dialect of Old Indo-Aryan, originating as Vedic Sanskrit and tracing its linguistic ancestry back to Proto-Indo-Iranian and Proto-Indo-European. Today it is listed as one of the 22 scheduled languages of India and is an official language of the state of Uttarakhand. As one of the oldest Indo-European languages for which substantial written documentation exists, Sanskrit holds a prominent position in Indo-European studies.
Besides its uses as language of religions, for what other application can Sanskrit be used?
A: lingua franca

Context and question: The most important archaeological discoveries in Sumer are a large number of tablets written in cuneiform. Sumerian writing, while proven to be not the oldest example of writing on earth, is considered to be a great milestone in the development of man's ability to not only create historical records but also in creating pieces of literature both in the form of poetic epics and stories as well as prayers and laws. Although pictures that is, hieroglyphs were first used, cuneiform and then Ideograms (where symbols were made to represent ideas) soon followed. Triangular or wedge-shaped reeds were used to write on moist clay. A large body of hundreds of thousands of texts in the Sumerian language have survived, such as personal or business letters, receipts, lexical lists, laws, hymns, prayers, stories, daily records, and even libraries full of clay tablets. Monumental inscriptions and texts on different objects like statues or bricks are also very common. Many texts survive in multiple copies because they were repeatedly transcribed by scribes-in-training. Sumerian continued to be the language of religion and law in Mesopotamia long after Semitic speakers had become dominant.
What were the most important discoveries for archaeologists from Sumer?
Answer: tablets written in cuneiform

Question: Larger SAMs may be deployed in fixed launchers, but can be towed/re-deployed at will. The SAMs launched by individuals are known in the United States as the Man-Portable Air Defence Systems (MANPADS). MANPADS of the former Soviet Union have been exported around the World, and can be found in use by many armed forces. Targets for non-ManPAD SAMs will usually be acquired by air-search radar, then tracked before/while a SAM is "locked-on" and then fired. Potential targets, if they are military aircraft, will be identified as friend or foe before being engaged. The developments in the latest and relatively cheap short-range missiles have begun to replace autocannons in this role.
Is there an answer to this question: Short range missiles are replacing what weapons?

Answer: autocannons

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Boundaries can be inclusive or exclusive depending on how they are perceived by other people. An exclusive boundary arises, for example, when a person adopts a marker that imposes restrictions on the behaviour of others. An inclusive boundary is created, by contrast, by the use of a marker with which other people are ready and able to associate. At the same time, however, an inclusive boundary will also impose restrictions on the people it has included by limiting their inclusion within other boundaries. An example of this is the use of a particular language by a newcomer in a room full of people speaking various languages. Some people may understand the language used by this person while others may not. Those who do not understand it might take the newcomer's use of this particular language merely as a neutral sign of identity. But they might also perceive it as imposing an exclusive boundary that is meant to mark them off from her. On the other hand, those who do understand the newcomer's language could take it as an inclusive boundary, through which the newcomer associates herself with them to the exclusion of the other people present. Equally, however, it is possible that people who do understand the newcomer but who also speak another language may not want to speak the newcomer's language and so see her marker as an imposition and a negative boundary. It is possible that the newcomer is either aware or unaware of this, depending on whether she herself knows other languages or is conscious of the plurilingual quality of the people there and is respectful of it or not.
What are the two types of group boundaries?
A:
inclusive or exclusive