Problem: Relations between the Rus' and Byzantines became more complex after Oleg took control over Kiev, reflecting commercial, cultural, and military concerns. The wealth and income of the Rus' depended heavily upon trade with Byzantium. Constantine Porphyrogenitus described the annual course of the princes of Kiev, collecting tribute from client tribes, assembling the product into a flotilla of hundreds of boats, conducting them down the Dnieper to the Black Sea, and sailing to the estuary of the Dniester, the Danube delta, and on to Constantinople. On their return trip they would carry silk fabrics, spices, wine, and fruit. The importance of this trade relationship led to military action when disputes arose. The Primary Chronicle reports that the Rus' attacked Constantinople again in 907, probably to secure trade access. The Chronicle glorifies the military prowess and shrewdness of Oleg, an account imbued with legendary detail. Byzantine sources do not mention the attack, but a pair of treaties in 907 and 911 set forth a trade agreement with the Rus', the terms suggesting pressure on the Byzantines, who granted the Rus' quarters and supplies for their merchants and tax-free trading privileges in Constantinople.
When did the Rus attack the Constantinole once again?
The answer is the following: 907

Problem: Facial hair in males normally appears in a specific order during puberty: The first facial hair to appear tends to grow at the corners of the upper lip, typically between 14 to 17 years of age. It then spreads to form a moustache over the entire upper lip. This is followed by the appearance of hair on the upper part of the cheeks, and the area under the lower lip. The hair eventually spreads to the sides and lower border of the chin, and the rest of the lower face to form a full beard. As with most human biological processes, this specific order may vary among some individuals. Facial hair is often present in late adolescence, around ages 17 and 18, but may not appear until significantly later. Some men do not develop full facial hair for 10 years after puberty. Facial hair continues to get coarser, darker and thicker for another 24 years after puberty.
For how long does facial hair continue to get darker, coarser, and thicker?
The answer is the following: 24 years after puberty

Problem: The experience of pain has many cultural dimensions. For instance, the way in which one experiences and responds to pain is related to sociocultural characteristics, such as gender, ethnicity, and age. An aging adult may not respond to pain in the way that a younger person would. Their ability to recognize pain may be blunted by illness or the use of multiple prescription drugs. Depression may also keep the older adult from reporting they are in pain. The older adult may also quit doing activities they love because it hurts too much. Decline in self-care activities (dressing, grooming, walking, etc.) may also be indicators that the older adult is experiencing pain. The older adult may refrain from reporting pain because they are afraid they will have to have surgery or will be put on a drug they might become addicted to. They may not want others to see them as weak, or may feel there is something impolite or shameful in complaining about pain, or they may feel the pain is deserved punishment for past transgressions.
Aging adult's ability to recognize pain may be blunted by what?
The answer is the following: illness

Problem: Bal-musette is a style of French music and dance that first became popular in Paris in the 1870s and 1880s; by 1880 Paris had some 150 dance halls in the working-class neighbourhoods of the city. Patrons danced the bourree to the accompaniment of the cabrette (a bellows-blown bagpipe locally called a "musette") and often the vielle a roue (hurdy-gurdy) in the cafes and bars of the city. Parisian and Italian musicians who played the accordion adopted the style and established themselves in Auvergnat bars especially in the 19th arrondissement, and the romantic sounds of the accordion has since become one of the musical icons of the city. Paris became a major centre for jazz and still attracts jazz musicians from all around the world to its clubs and cafes.
in 1880, how many dance halls were in Paris?
The answer is the following:
150