Problem: These years saw an evolution in the participation of Empress Dowager Cixi (Wade–Giles: Tz'u-Hsi) in state affairs. She entered the imperial palace in the 1850s as a concubine to the Xianfeng Emperor (r. 1850–1861) and came to power in 1861 after her five-year-old son, the Tongzhi Emperor ascended the throne. She, the Empress Dowager Ci'an (who had been Xianfeng's empress), and Prince Gong (a son of the Daoguang Emperor), staged a coup that ousted several regents for the boy emperor. Between 1861 and 1873, she and Ci'an served as regents, choosing the reign title "Tongzhi" (ruling together). Following the emperor's death in 1875, Cixi's nephew, the Guangxu Emperor, took the throne, in violation of the dynastic custom that the new emperor be of the next generation, and another regency began. In the spring of 1881, Ci'an suddenly died, aged only forty-three, leaving Cixi as sole regent. 
When did Tongzhi Emperor die?
The answer is the following: 1875

Problem: European colonists created treaties with Indigenous American tribes requesting the return of any runaway slaves. For example, in 1726, the British governor of New York exacted a promise from the Iroquois to return all runaway slaves who had joined them. This same promise was extracted from the Huron Nation in 1764, and from the Delaware Nation in 1765, though there is no record of slaves ever being returned. Numerous advertisements requested the return of African Americans who had married Indigenous Americans or who spoke an Indigenous American language. The primary exposure that Africans and Indigenous Americans had to each other came through the institution of slavery. Indigenous Americans learned that Africans had what Indigenous Americans considered 'Great Medicine' in their bodies because Africans were virtually immune to the Old-World diseases that were decimating most native populations. Because of this, many tribes encouraged marriage between the two groups, to create stronger, healthier children from the unions.
Who did colonists ask for help in returning runaway slaves?
The answer is the following: Indigenous American tribes

Problem: The character of New York's large residential districts is often defined by the elegant brownstone rowhouses and townhouses and shabby tenements that were built during a period of rapid expansion from 1870 to 1930. In contrast, New York City also has neighborhoods that are less densely populated and feature free-standing dwellings. In neighborhoods such as Riverdale (in the Bronx), Ditmas Park (in Brooklyn), and Douglaston (in Queens), large single-family homes are common in various architectural styles such as Tudor Revival and Victorian.
What type of housing structure makes up most of the large residential districts of NYC?
The answer is the following: brownstone rowhouses

Problem: Dell announced a change campaign called "Dell 2.0," reducing the number of employees and diversifying the company's products. While chairman of the board after relinquishing his CEO position, Michael Dell still had significant input in the company during Rollins' years as CEO. With the return of Michael Dell as CEO, the company saw immediate changes in operations, the exodus of many senior vice-presidents and new personnel brought in from outside the company. Michael Dell announced a number of initiatives and plans (part of the "Dell 2.0" initiative) to improve the company's financial performance. These include elimination of 2006 bonuses for employees with some discretionary awards, reduction in the number of managers reporting directly to Michael Dell from 20 to 12, and reduction of "bureaucracy". Jim Schneider retired as CFO and was replaced by Donald Carty, as the company came under an SEC probe for its accounting practices.
Michael Dell removed employee bonuses from what year with his new incentive?
The answer is the following:
2006