Problem: Circadian rhythm:

What drove circadian rhythms to evolve has been an enigmatic question. Previous hypotheses emphasized that photosensitive proteins and circadian rhythms may have originated together in the earliest cells, with the purpose of protecting replicating DNA from high levels of damaging ultraviolet radiation during the daytime. As a result, replication was relegated to the dark. However, evidence for this is lacking, since the simplest organisms with a circadian rhythm, the cyanobacteria, do the opposite of this - they divide more in the daytime. Recent studies instead highlight the importance of co-evolution of redox proteins with circadian oscillators in all three kingdoms of life following the Great Oxidation Event approximately 2.3 billion years ago. The current view is that circadian changes in environmental oxygen levels and the production of reactive oxygen species (ROS) in the presence of daylight are likely to have driven a need to evolve circadian rhythms to preempt, and therefore counteract, damaging redox reactions on a daily basis.

What event occurred approximately 2.3 million years ago?
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A: unanswerable


Problem: Endangered Species Act:

The "Safe Harbor" agreement is a voluntary agreement between the private landowner and FWS. The landowner agrees to alter the property to benefit or even attract a listed or proposed species in exchange for assurances that the FWS will permit future "takes" above a pre-determined level. The policy relies on the "enhancement of survival" provision of Section §1539(a)(1)(A). A landowner can have either a "Safe Harbor" agreement or an Incidental Take Permit, or both. The policy was developed by the Clinton Administration in 1999.

What form of agreement can a landowner no longer have if they acquire an ITP?
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A: unanswerable


Problem: Sichuan:

The Yangtze River and its tributaries flows through the mountains of western Sichuan and the Sichuan Basin; thus, the province is upstream of the great cities that stand along the Yangtze River further to the east, such as Chongqing, Wuhan, Nanjing and Shanghai. One of the major tributaries of the Yangtze within the province is the Min River of central Sichuan, which joins the Yangtze at Yibin. Sichuan's 4 main rivers, as Sichuan means literally, are Jaling Jiang, Tuo Jiang, Yalong Jiang, and Jinsha Jiang.

What province is downstream from the large cities along the Yangtze?
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A: unanswerable


Problem: Egypt:

The Egyptian military has dozens of factories manufacturing weapons as well as consumer goods. The Armed Forces' inventory includes equipment from different countries around the world. Equipment from the former Soviet Union is being progressively replaced by more modern US, French, and British equipment, a significant portion of which is built under license in Egypt, such as the M1 Abrams tank.[citation needed] Relations with Russia have improved significantly following Mohamed Morsi's removal and both countries have worked since then to strengthen military and trade ties among other aspects of bilateral co-operation. Relations with China have also improved considerably. In 2014, Egypt and China have established a bilateral "comprehensive strategic partnership".

How many factories does Egyptian military have?
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A:
dozens