In the following year, Bell became professor of Vocal Physiology and Elocution at the Boston University School of Oratory. During this period, he alternated between Boston and Brantford, spending summers in his Canadian home. At Boston University, Bell was "swept up" by the excitement engendered by the many scientists and inventors residing in the city. He continued his research in sound and endeavored to find a way to transmit musical notes and articulate speech, but although absorbed by his experiments, he found it difficult to devote enough time to experimentation. While days and evenings were occupied by his teaching and private classes, Bell began to stay awake late into the night, running experiment after experiment in rented facilities at his boarding house. Keeping "night owl" hours, he worried that his work would be discovered and took great pains to lock up his notebooks and laboratory equipment. Bell had a specially made table where he could place his notes and equipment inside a locking cover. Worse still, his health deteriorated as he suffered severe headaches. Returning to Boston in fall 1873, Bell made a fateful decision to concentrate on his experiments in sound.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What health condition did Bell start to have?
Ah, so.. headaches

With the onset of the Crusades in 1095, and the expulsions from England (1290), France (1394), and parts of Germany (15th century), Jewish migration pushed eastward into Poland (10th century), Lithuania (10th century), and Russia (12th century). Over this period of several hundred years, some have suggested, Jewish economic activity was focused on trade, business management, and financial services, due to several presumed factors: Christian European prohibitions restricting certain activities by Jews, preventing certain financial activities (such as "usurious" loans) between Christians, high rates of literacy, near universal male education, and ability of merchants to rely upon and trust family members living in different regions and countries.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): As Jews were expelled from England, France, and parts of Germany they head into which three countries?
Ah, so.. Poland (10th century), Lithuania (10th century), and Russia (12th century)

A number of technologies allow asphalt/bitumen to be mixed at much lower temperatures. These involve mixing with petroleum solvents to form "cutbacks" with reduced melting point, or mixtures with water to turn the asphalt/bitumen into an emulsion. Asphalt emulsions contain up to 70% asphalt/bitumen and typically less than 1.5% chemical additives. There are two main types of emulsions with different affinity for aggregates, cationic and anionic. Asphalt emulsions are used in a wide variety of applications. Chipseal involves spraying the road surface with asphalt emulsion followed by a layer of crushed rock, gravel or crushed slag. Slurry seal involves the creation of a mixture of asphalt emulsion and fine crushed aggregate that is spread on the surface of a road. Cold-mixed asphalt can also be made from asphalt emulsion to create pavements similar to hot-mixed asphalt, several inches in depth and asphalt emulsions are also blended into recycled hot-mix asphalt to create low-cost pavements.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): How many types of chipseals with different affinities are there?
Ah, so..
unanswerable