Question: Motors have very little room for electrical insulation so they generally have low voltage ratings. Because transformers (prior to the development of power electronics) cannot step down DC voltages, trains were supplied with a relatively low DC voltage that the motors can use directly. The most common DC voltages are listed in the previous section. Third (and fourth) rail systems almost always use voltages below 1 kV for safety reasons while overhead wires usually use higher voltages for efficiency. ("Low" voltage is relative; even 600 V can be instantly lethal when touched.)
Is there an answer to this question: How many volts can be considered nonlethal when touched?

Answer: unanswerable


Question: The study of the Quran and the Hadith thrived in such a scholarly atmosphere. Philosophy, Fiqh and theology (kalaam) were further developed, most noticeably by Avicenna and his opponents. Al-Razi and Al-Farabi had provided methodology and knowledge in medicine and philosophy. Avicenna had access to the great libraries of Balkh, Khwarezm, Gorgan, Rey, Isfahan and Hamadan. Various texts (such as the 'Ahd with Bahmanyar) show that he debated philosophical points with the greatest scholars of the time. Aruzi Samarqandi describes how before Avicenna left Khwarezm he had met Al-Biruni (a famous scientist and astronomer), Abu Nasr Iraqi (a renowned mathematician), Abu Sahl Masihi (a respected philosopher) and Abu al-Khayr Khammar (a great physician).
Is there an answer to this question: What is the name of one library that Avicenna had access to?

Answer: Hamadan


Question: While the majority of flowers are perfect or hermaphrodite (having both pollen and ovule producing parts in the same flower structure), flowering plants have developed numerous morphological and physiological mechanisms to reduce or prevent self-fertilization. Heteromorphic flowers have short carpels and long stamens, or vice versa, so animal pollinators cannot easily transfer pollen to the pistil (receptive part of the carpel). Homomorphic flowers may employ a biochemical (physiological) mechanism called self-incompatibility to discriminate between self and non-self pollen grains. In other species, the male and female parts are morphologically separated, developing on different flowers.
Is there an answer to this question: What do homomorphic flowers have to make it harder to be pollinated by animals?

Answer: unanswerable


Question: In the United States, there was a movement to resettle American free blacks and freed slaves in Africa. The American Colonization Society was founded in 1816 in Washington, DC for this purpose, by a group of prominent politicians and slaveholders. But its membership grew to include mostly people who supported abolition of slavery. Slaveholders wanted to get free people of color out of the South, where they were thought to threaten the stability of the slave societies. Some abolitionists collaborated on relocation of free blacks, as they were discouraged by discrimination against them in the North and believed they would never be accepted in the larger society. Most African Americans, who were native-born by this time, wanted to improve conditions in the United States rather than emigrate. Leading activists in the North strongly opposed the ACS, but some free blacks were ready to try a different environment.
Is there an answer to this question: How did many African Americans feel after the abolition of slavery?

Answer:
unanswerable