Problem: Incandescent light bulb:

An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light with a wire filament heated to a high temperature, by passing an electric current through it, until it glows with visible light (incandescence). The hot filament is protected from oxidation with a glass or quartz bulb that is filled with inert gas or evacuated. In a halogen lamp, filament evaporation is prevented by a chemical process that redeposits metal vapor onto the filament, extending its life. The light bulb is supplied with electric current by feed-through terminals or wires embedded in the glass. Most bulbs are used in a socket which provides mechanical support and electrical connections.

What part of a halogen light bulb does not supply electric current?
---
A: unanswerable


Problem: The second generation of the system, officially called the BeiDou Navigation Satellite System (BDS) and also known as COMPASS or BeiDou-2, will be a global satellite navigation system consisting of 35 satellites, and is under construction as of January 2015[update]. It became operational in China in December 2011, with 10 satellites in use, and began offering services to customers in the Asia-Pacific region in December 2012. It is planned to begin serving global customers upon its completion in 2020.
What is the name of the second generation of BDS?
---
Answer: BeiDou Navigation Satellite System


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Ann Arbor has a long history of openness to marijuana, given Ann Arbor's decriminalization of cannabis, the large number of medical marijuana dispensaries in the city (one dispensary, called People's Co-op, was directly across the street from Michigan Stadium until zoning forced it to move one mile to the west), the large number of pro-marijuana residents, and the annual Hash Bash: an event that is held on the first Saturday of April. Until (at least) the successful passage of Michigan's medical marijuana law, the event had arguably strayed from its initial intent, although for years, a number of attendees have received serious legal responses due to marijuana use on University of Michigan property, which does not fall under the City's progressive and compassionate ticketing program.
What was legal to smoke on the University of Michigan property/
A: unanswerable


Context and question: Sometimes, poly-sided matches that pit every one for themselves will incorporate tagging rules. Outside of kayfabe, this is done to give wrestlers a break from the action (as these matches tend to go on for long periods of time), and to make the action in the ring easier to choreograph. One of the most mainstream examples of this is the four-corner match, the most common type of match in the WWE before it was replaced with its equivalent fatal four-way; four wrestlers, each for themselves, fight in a match, but only two wrestlers can be in the match at any given time. The other two are positioned in the corner, and tags can be made between any two wrestlers.
What was the most common type of match before the fatal four-way? 
Answer: four-corner match


Question: An additional 4.6 billion tonnes of uranium are estimated to be in sea water (Japanese scientists in the 1980s showed that extraction of uranium from sea water using ion exchangers was technically feasible). There have been experiments to extract uranium from sea water, but the yield has been low due to the carbonate present in the water. In 2012, ORNL researchers announced the successful development of a new absorbent material dubbed HiCap which performs surface retention of solid or gas molecules, atoms or ions and also effectively removes toxic metals from water, according to results verified by researchers at Pacific Northwest National Laboratory.
Is there an answer to this question: What did ORNL call their material that performs surface retention on liquid molecules?

Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The divisions between all these groups are approximate and their boundaries are not always clear. The Mizrahim for example, are a heterogeneous collection of North African, Central Asian, Caucasian, and Middle Eastern Jewish communities that are no closer related to each other than they are to any of the earlier mentioned Jewish groups. In modern usage, however, the Mizrahim are sometimes termed Sephardi due to similar styles of liturgy, despite independent development from Sephardim proper. Thus, among Mizrahim there are Egyptian Jews, Iraqi Jews, Lebanese Jews, Kurdish Jews, Libyan Jews, Syrian Jews, Bukharian Jews, Mountain Jews, Georgian Jews, Iranian Jews and various others. The Teimanim from Yemen are sometimes included, although their style of liturgy is unique and they differ in respect to the admixture found among them to that found in Mizrahim. In addition, there is a differentiation made between Sephardi migrants who established themselves in the Middle East and North Africa after the expulsion of the Jews from Spain and Portugal in the 1490s and the pre-existing Jewish communities in those regions.
When were the Jews welcomed into Spain and Portugal?
A:
unanswerable