Problem: Time:

Another solution to the problem of causality-based temporal paradoxes is that such paradoxes cannot arise simply because they have not arisen. As illustrated in numerous works of fiction, free will either ceases to exist in the past or the outcomes of such decisions are predetermined. As such, it would not be possible to enact the grandfather paradox because it is a historical fact that your grandfather was not killed before his child (your parent) was conceived. This view doesn't simply hold that history is an unchangeable constant, but that any change made by a hypothetical future time traveler would already have happened in his or her past, resulting in the reality that the traveler moves from. More elaboration on this view can be found in the Novikov self-consistency principle.

Why can paradoxes arise?
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A: unanswerable


Problem: Green:

Animals typically use the color green as camouflage, blending in with the chlorophyll green of the surrounding environment. Green animals include, especially, amphibians, reptiles, and some fish, birds and insects. Most fish, reptiles, amphibians, and birds appear green because of a reflection of blue light coming through an over-layer of yellow pigment. Perception of color can also be affected by the surrounding environment. For example, broadleaf forests typically have a yellow-green light about them as the trees filter the light. Turacoverdin is one chemical which can cause a green hue in birds, especially. Invertebrates such as insects or mollusks often display green colors because of porphyrin pigments, sometimes caused by diet. This can causes their feces to look green as well. Other chemicals which generally contribute to greenness among organisms are flavins (lychochromes) and hemanovadin. Humans have imitated this by wearing green clothing as a camouflage in military and other fields. Substances that may impart a greenish hue to one's skin include biliverdin, the green pigment in bile, and ceruloplasmin, a protein that carries copper ions in chelation.

Why do most fish appear blue?
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A: unanswerable


Problem: Napoleon:

Upon graduating in September 1785, Bonaparte was commissioned a second lieutenant in La Fère artillery regiment.[note 4] He served in Valence and Auxonne until after the outbreak of the Revolution in 1789, and took nearly two years' leave in Corsica and Paris during this period. At this time, he was a fervent Corsican nationalist, and wrote to Corsican leader Pasquale Paoli in May 1789, "As the nation was perishing I was born. Thirty thousand Frenchmen were vomited on to our shores, drowning the throne of liberty in waves of blood. Such was the odious sight which was the first to strike me."

When did Napoleon graduate?
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A: September 1785


Problem: Queen Victoria:

In 1897, Victoria had written instructions for her funeral, which was to be military as befitting a soldier's daughter and the head of the army, and white instead of black. On 25 January, Edward VII, the Kaiser and Prince Arthur, Duke of Connaught, helped lift her body into the coffin. She was dressed in a white dress and her wedding veil. An array of mementos commemorating her extended family, friends and servants were laid in the coffin with her, at her request, by her doctor and dressers. One of Albert's dressing gowns was placed by her side, with a plaster cast of his hand, while a lock of John Brown's hair, along with a picture of him, was placed in her left hand concealed from the view of the family by a carefully positioned bunch of flowers. Items of jewellery placed on Victoria included the wedding ring of John Brown's mother, given to her by Brown in 1883. Her funeral was held on Saturday, 2 February, in St George's Chapel, Windsor Castle, and after two days of lying-in-state, she was interred beside Prince Albert in Frogmore Mausoleum at Windsor Great Park. As she was laid to rest at the mausoleum, it began to snow.

When did John Brown give Victoria his mother's wedding ring? 
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A:
1883