Problem: The percentage of adults using a prescription sleep aid increases with age. During 20052010, about 4% of U.S. adults aged 20 and over reported that they took prescription sleep aids in the past 30 days. Rates of use were lowest among the youngest age group (those aged 2039) at about 2%, increased to 6% among those aged 5059, and reached 7% among those aged 80 and over. More adult women (5.0%) reported using prescription sleep aids than adult men (3.1%). Non-Hispanic white adults reported higher use of sleep aids (4.7%) than non-Hispanic black (2.5%) and Mexican-American (2.0%) adults. No difference was shown between non-Hispanic black adults and Mexican-American adults in use of prescription sleep aids.

Which age group used more prescription sleep aids, 20-39 age group, or 50-59 age group?
Answer: 50-59 age group

Problem: Paraguay relies almost solely on hydroelectric power to meet its energy needs. The Itaipu Dam, completed in 1984, has the world's second largest power-generating capacity: 13.3 gigawatts. The dam is located on the Paraguay River, and Paraguay and Brazil evenly share the ownership, operation, and electricity generated. Additionally, Paraguay co-owns another major hydropower plant, Yacyreta, with Argentina. Paraguay uses only a small portion of the energy it generates through Itaipu and Yacyreta. In 2002 Paraguay generated more than 48 billion kilowatt-hours of energy. It consumed only 2.5 billion kilowatt-hours while exporting 45.9 billion kilowatt-hours. Paraguay will have even more hydroelectricity to export when planned new turbines are installed at Itaipu and the Yacyreta dam is fully completed. In 2007 electricity production rose to 70 TWh, and exports reached 64 TWh which put Paraguay in second place worldwide as an exporter of electrical power . Paraguay has no oil reserves; it relies on imported oil to meet its limited need for oil-produced energy. The Paraguayan government owns Petroleos Paraguayos, which is responsible for all distribution of oil products. The state accepts bids from international oil companies, selecting a few companies annually to meet the country's demand. Presently, Paraguay does not produce or consume natural gas, but consumes LPG imported mainly from Argentina.

Who does Paraguay share ownership of Yacyreta with?
Answer: Argentina

Problem: Soon after the Battle of Warsaw the Bolsheviks sued for peace. The Poles, exhausted, constantly pressured by the Western governments and the League of Nations, and with its army controlling the majority of the disputed territories, were willing to negotiate. The Soviets made two offers: one on 21 September and the other on 28 September. The Polish delegation made a counteroffer on 2 October. On the 5th, the Soviets offered amendments to the Polish offer, which Poland accepted. The Preliminary Treaty of Peace and Armistice Conditions between Poland on one side and Soviet Ukraine and Soviet Russia on the other was signed on 12 October, and the armistice went into effect on 18 October. Ratifications were exchanged at Liepaja on 2 November. Long negotiations of the final peace treaty ensued. Meanwhile, Petliura's Ukrainian forces, which now numbered 23,000 soldiers and controlled territories immediately to the east of Poland, planned an offensive in Ukraine for 11 November but were attacked by the Bolsheviks on 10 November. By 21 November, after several battles, they were driven into Polish-controlled territory.

How many days after the Polish accepted the Soviets' amendments was the Preliminary Treaty of Peace and Armistice Conditions signed?
Answer: 7

Problem: In 1960 Random House acquired Alfred A. Knopf. It is believed that the decision to sell was prompted by Alfred A. Knopf, Jr., leaving Knopf to found his own book company, Atheneum Books in 1959. Since its founding, Knopf has paid close attention to design and typography, employing notable designers and typographers including William Addison Dwiggins, Harry Ford, Steven Heller, Chip Kidd, Lorraine Louie, Bruce Rogers, Rudolf Ruzicka, and Beatrice Warde. Knopf books conclude with an unnumbered page titled "A Note on the Type", which describes the history of the typeface used for the book. In addition, Knopf books date the year of the book's current printing on the title page. Knopf published textbooks until 1988, when Random House's schools and colleges division was sold to McGraw-Hill. In 1991, Knopf revived the "Everyman's Library" series, originally published in England in the early 20th century. This series consists of classics of world literature in affordable hardcover editions. The series has grown over the years to include lines of Children's Classics and Pocket Poets. Random House was acquired by Bertelsmann in 1998. In late 2008 and early 2009, the Knopf Publishing Group merged with Doubleday to form the Knopf Doubleday Publishing Group. Random House has been owned since its 2013 merger of Penguin Group by Penguin Random House, a joint venture between Bertelsmann and Pearson PLC . Many of Knopf's hardcover books are published later as Vintage paperbacks. Vintage Books is a sister imprint of Random House. In 2015, Knopf celebrated its 100th Anniversary by publishing a commemorative book, Alfred A. Knopf, 1915-2015: A Century of Publishing.

Which appears first in a Knopf book, the year of the book's current printing, or a description of the history of the typeface?
Answer:
book's current printing