Problem: Light-emitting diode:

Assistive listening devices in many theaters and similar spaces use arrays of infrared LEDs to send sound to listeners' receivers. Light-emitting diodes (as well as semiconductor lasers) are used to send data over many types of fiber optic cable, from digital audio over TOSLINK cables to the very high bandwidth fiber links that form the Internet backbone. For some time, computers were commonly equipped with IrDA interfaces, which allowed them to send and receive data to nearby machines via infrared.

Where are infrared non-LEDs used in everyday life?
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A: unanswerable

Problem: In 2012, news was released about a new farming site discovered in Munam-ri, Goseong, Gangwon Province, South Korea, which may be the earliest farmland known to date in east Asia. "No remains of an agricultural field from the Neolithic period have been found in any East Asian country before, the institute said, adding that the discovery reveals that the history of agricultural cultivation at least began during the period on the Korean Peninsula". The farm was dated between 3600 and 3000 B.C. Pottery, stone projectile points, and possible houses were also found. "In 2002, researchers discovered prehistoric earthenware, jade earrings, among other items in the area". The research team will perform accelerator mass spectrometry (AMS) dating to retrieve a more precise date for the site.
When did researchers discover prehistoric plants?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Dell was listed at number 51 in the Fortune 500 list, until 2014. After going private in 2013, the newly confidential nature of its financial information prevents the company from being ranked by Fortune. In 2014 it was the third largest PC vendor in the world after Lenovo and HP. Dell is currently the #1 shipper of PC monitors in the world. Dell is the sixth largest company in Texas by total revenue, according to Fortune magazine. It is the second largest non-oil company in Texas behind AT&T and the largest company in the Greater Austin area. It was a publicly traded company (NASDAQ: DELL), as well as a component of the NASDAQ-100 and S&P 500, until it was taken private in a leveraged buyout which closed on October 30, 2013.
Dell is currently the #1 shipper of what?
A: PC monitors

Context and question: The Tanana Valley is another notable agricultural locus, especially the Delta Junction area, about 100 miles (160 km) southeast of Fairbanks, with a sizable concentration of farms growing agronomic crops; these farms mostly lie north and east of Fort Greely. This area was largely set aside and developed under a state program spearheaded by Hammond during his second term as governor. Delta-area crops consist predominately of barley and hay. West of Fairbanks lies another concentration of small farms catering to restaurants, the hotel and tourist industry, and community-supported agriculture.
Which crops are produced in the Delta-area?
Answer: barley and hay

Question: The root system and the shoot system are interdependent the usually nonphotosynthetic root system depends on the shoot system for food, and the usually photosynthetic shoot system depends on water and minerals from the root system. Cells in each system are capable of creating cells of the other and producing adventitious shoots or roots. Stolons and tubers are examples of shoots that can grow roots. Roots that spread out close to the surface, such as those of willows, can produce shoots and ultimately new plants. In the event that one of the systems is lost, the other can often regrow it. In fact it is possible to grow an entire plant from a single leaf, as is the case with Saintpaulia, or even a single cell which can dedifferentiate into a callus (a mass of unspecialised cells) that can grow into a new plant. In vascular plants, the xylem and phloem are the conductive tissues that transport resources between shoots and roots. Roots are often adapted to store food such as sugars or starch, as in sugar beets and carrots.
Is there an answer to this question: What do the roots get from the shoots?

Answer: food

Problem: Jehovah%27s Witnesses:

Meetings for worship and study are held at Kingdom Halls, which are typically functional in character, and do not contain religious symbols. Witnesses are assigned to a congregation in whose "territory" they usually reside and attend weekly services they refer to as "meetings" as scheduled by congregation elders. The meetings are largely devoted to study of Watch Tower Society literature and the Bible. The format of the meetings is established by the religion's headquarters, and the subject matter for most meetings is the same worldwide. Congregations meet for two sessions each week comprising five distinct meetings that total about three-and-a-half hours, typically gathering mid-week (three meetings) and on the weekend (two meetings). Prior to 2009, congregations met three times each week; these meetings were condensed, with the intention that members dedicate an evening for "family worship". Gatherings are opened and closed with kingdom songs (hymns) and brief prayers. Twice each year, Witnesses from a number of congregations that form a "circuit" gather for a one-day assembly. Larger groups of congregations meet once a year for a three-day "regional convention", usually at rented stadiums or auditoriums. Their most important and solemn event is the commemoration of the "Lord's Evening Meal", or "Memorial of Christ's Death" on the date of the Jewish Passover.

What are Jehovah Witnesses' gatherings opened and closed with?
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A:
songs (hymns) and brief prayers