The hourglass uses the flow of sand to measure the flow of time. They were used in navigation. Ferdinand Magellan used 18 glasses on each ship for his circumnavigation of the globe (1522). Incense sticks and candles were, and are, commonly used to measure time in temples and churches across the globe. Waterclocks, and later, mechanical clocks, were used to mark the events of the abbeys and monasteries of the Middle Ages. Richard of Wallingford (12921336), abbot of St. Alban's abbey, famously built a mechanical clock as an astronomical orrery about 1330. Great advances in accurate time-keeping were made by Galileo Galilei and especially Christiaan Huygens with the invention of pendulum driven clocks along with the invention of the minute hand by Jost Burgi.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Which abbot of St. Alban's abbey built a mechanical clock around 1330?
Ah, so.. Richard of Wallingford

The Chronicle provides a mythic tale of Oleg's death. A sorcerer prophesies that the death of the Grand Prince would be associated with a certain horse. Oleg has the horse sequestered, and it later dies. Oleg goes to visit the horse and stands over the carcass, gloating that he had outlived the threat, when a snake strikes him from among the bones, and he soon becomes ill and dies. The Chronicle reports that Prince Igor succeeded Oleg in 913, and after some brief conflicts with the Drevlians and the Pechenegs, a period of peace ensued for over twenty years.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who conquered and killed Oleg?
Ah, so.. unanswerable

In nature, the red color of blood comes from hemoglobin, the iron-containing protein found in the red blood cells of all vertebrates. The red color of the Grand Canyon and other geological features is caused by hematite or red ochre, both forms of iron oxide. It also causes the red color of the planet Mars. The red sky at sunset and sunrise is caused by an optical effect known as Rayleigh scattering, which, when the sun is low or below the horizon, increases the red-wavelength light that reaches the eye. The color of autumn leaves is caused by pigments called anthocyanins, which are produced towards the end of summer, when the green chlorophyll is no longer produced. One to two percent of the human population has red hair; the color is produced by high levels of the reddish pigment pheomelanin (which also accounts for the red color of the lips) and relatively low levels of the dark pigment eumelanin.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What causes the color of hematite and red ochre?
Ah, so..
iron oxide