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Native Americans in the United States make up 0.97% to 2% of the population. In the 2010 census, 2.9 million people self-identified as Native American, Native Hawaiian, and Alaska Native alone, and 5.2 million people identified as U.S. Native Americans, either alone or in combination with one or more ethnicity or other races. 1.8 million are recognized as enrolled tribal members.[citation needed] Tribes have established their own criteria for membership, which are often based on blood quantum, lineal descent, or residency. A minority of US Native Americans live in land units called Indian reservations. Some California and Southwestern tribes, such as the Kumeyaay, Cocopa, Pascua Yaqui and Apache span both sides of the USMexican border. Haudenosaunee people have the legal right to freely cross the USCanadian border. Athabascan, Tlingit, Haida, Tsimshian, Inupiat, Blackfeet, Nakota, Cree, Anishinaabe, Huron, Lenape, Mi'kmaq, Penobscot, and Haudenosaunee, among others live in both Canada and the US.
How many of the self-identified Native Americans are recognized as enrolled tribal members?
A: 1.8 million

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The mandolin has been used occasionally in rock music, first appearing in the psychedelic era of the late 1960s. Levon Helm of The Band occasionally moved from his drum kit to play mandolin, most notably on Rag Mama Rag, Rockin' Chair, and Evangeline. Ian Anderson of Jethro Tull played mandolin on Fat Man, from their second album, Stand Up, and also occasionally on later releases. Rod Stewart's 1971 No. 1 hit Maggie May features a significant mandolin riff. David Grisman played mandolin on two Grateful Dead songs on the American Beauty album, Friend of the Devil and Ripple, which became instant favorites among amateur pickers at jam sessions and campground gatherings. John Paul Jones and Jimmy Page both played mandolin on Led Zeppelin songs. The popular alt rock group Imagine Dragons feature the mandolin on a few of their songs, most prominently being It's Time. Dash Crofts of the soft rock duo Seals and Crofts extensively used mandolin in their repertoire during the 1970s. Styx released the song Boat on the River in 1980, which featured Tommy Shaw on vocals and mandolin. The song didn't chart in the United States but was popular in much of Europe and the Philippines.
Tommy Shaw sang and played the mandolin in which Styx song?
A: Boat on the River

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In 2005, Estonia joined the European Union's Nordic Battle Group. It has also shown continued interest in joining the Nordic Council. Whereas in 1992 Russia accounted for 92% of Estonia's international trade, today there is extensive economic interdependence between Estonia and its Nordic neighbours: three quarters of foreign investment in Estonia originates in the Nordic countries (principally Finland and Sweden), to which Estonia sends 42% of its exports (as compared to 6.5% going to Russia, 8.8% to Latvia, and 4.7% to Lithuania). On the other hand, the Estonian political system, its flat rate of income tax, and its non-welfare-state model distinguish it from the Nordic countries and their Nordic model, and indeed from many other European countries.
What percentage of Estonia exports are sent to Nordic countries?
A: 42%

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Commonly called 'light bulbs', lamps are the removable and replaceable part of a light fixture, which converts electrical energy into electromagnetic radiation. While lamps have traditionally been rated and marketed primarily in terms of their power consumption, expressed in watts, proliferation of lighting technology beyond the incandescent light bulb has eliminated the correspondence of wattage to the amount of light produced. For example, a 60 W incandescent light bulb produces about the same amount of light as a 13 W compact fluorescent lamp. Each of these technologies has a different efficacy in converting electrical energy to visible light. Visible light output is typically measured in lumens. This unit only quantifies the visible radiation, and excludes invisible infrared and ultraviolet light. A wax candle produces on the close order of 13 lumens, a 60 watt incandescent lamp makes around 700 lumens, and a 15-watt compact fluorescent lamp produces about 800 lumens, but actual output varies by specific design. Rating and marketing emphasis is shifting away from wattage and towards lumen output, to give the purchaser a directly applicable basis upon which to select a lamp.
What is the removable and replaceable part of a light fixture?
A:
light bulbs