Problem: Alfred North Whitehead:

The two volume biography of Whitehead by Victor Lowe is the most definitive presentation of the life of Whitehead. However, many details of Whitehead's life remain obscure because he left no Nachlass; his family carried out his instructions that all of his papers be destroyed after his death. Additionally, Whitehead was known for his "almost fanatical belief in the right to privacy", and for writing very few personal letters of the kind that would help to gain insight on his life. This led to Lowe himself remarking on the first page of Whitehead's biography, "No professional biographer in his right mind would touch him."

What did the author of Whitehead's biography comment on the first page regarding the ease of obtaining information about Whitehead?
---
A: unanswerable


Problem: In the 5th-century Ravenna, the capital of the Western Roman Empire, became the center of late Roman mosaic art. The Mausoleum of Galla Placidia was decorated with mosaics of high artistic quality in 425–430. The vaults of the small, cross-shaped structure are clad with mosaics on blue background. The central motif above the crossing is a golden cross in the middle of the starry sky. Another great building established by Galla Placidia was the church of San Giovanni Evangelista. She erected it in fulfillment of a vow that she made having escaped from a deadly storm in 425 on the sea voyage from Constantinople to Ravenna. The mosaics depicted the storm, portraits of members of the western and eastern imperial family and the bishop of Ravenna, Peter Chrysologus. They are known only from Renaissance sources because almost all were destroyed in 1747.
In the 5th century what was the capital of the Western Roman Empire?
---
Answer: Ravenna


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The majority of studies indicate antibiotics do interfere with contraceptive pills, such as clinical studies that suggest the failure rate of contraceptive pills caused by antibiotics is very low (about 1%). In cases where antibacterials have been suggested to affect the efficiency of birth control pills, such as for the broad-spectrum antibacterial rifampicin, these cases may be due to an increase in the activities of hepatic liver enzymes' causing increased breakdown of the pill's active ingredients. Effects on the intestinal flora, which might result in reduced absorption of estrogens in the colon, have also been suggested, but such suggestions have been inconclusive and controversial. Clinicians have recommended that extra contraceptive measures be applied during therapies using antibacterials that are suspected to interact with oral contraceptives.
What do oral contraceptives reduce?
A: unanswerable


Context and question: While other companies were moving on to 32-bit systems, Rare and Nintendo proved that the SNES was still a strong contender in the market. In November 1994, Rare released Donkey Kong Country, a platform game featuring 3D models and textures pre-rendered on SGI workstations. With its detailed graphics, fluid animation and high-quality music, Donkey Kong Country rivaled the aesthetic quality of games that were being released on newer 32-bit CD-based consoles. In the last 45 days of 1994, the game sold 6.1 million units, making it the fastest-selling video game in history to that date. This game sent a message that early 32-bit systems had little to offer over the SNES, and helped make way for the more advanced consoles on the horizon.
How did Donkey Kong Country's quality compare to games on newer consoles?
Answer: detailed graphics, fluid animation and high-quality music


Question: Energy sources unsuitable for mobile power plants, such as nuclear power, renewable hydroelectricity, or wind power can be used. According to widely accepted global energy reserve statistics, the reserves of liquid fuel are much less than gas and coal (at 42, 167 and 416 years respectively). Most countries with large rail networks do not have significant oil reserves and those that did, like the United States and Britain, have exhausted much of their reserves and have suffered declining oil output for decades. Therefore, there is also a strong economic incentive to substitute other fuels for oil. Rail electrification is often considered an important route towards consumption pattern reform. However, there are no reliable, peer-reviewed studies available to assist in rational public debate on this critical issue, although there are untranslated Soviet studies from the 1980s.
Is there an answer to this question: Most countries with small rail networks do not have what?

Answer: unanswerable


QUES: There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; they both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized, with 68mCu the longest-lived with a half-life of 3.8 minutes. Isotopes with a mass number above 64 decay by β−, whereas those with a mass number below 64 decay by β+. 64Cu, which has a half-life of 12.7 hours, decays both ways.

What are the two dangerous isotopes of copper?
What is the answer?
ANS:
unanswerable