Problem: Aircraft carrier:

Conventional ("tailhook") aircraft rely upon a landing signal officer (LSO, radio call sign paddles) to monitor the aircraft's approach, visually gauge glideslope, attitude, and airspeed, and transmit that data to the pilot. Before the angled deck emerged in the 1950s, LSOs used colored paddles to signal corrections to the pilot (hence the nickname). From the late 1950s onward, visual landing aids such as Optical Landing System have provided information on proper glide slope, but LSOs still transmit voice calls to approaching pilots by radio.

Which visual landing aids have provided information on proper glide slope since the late 1940's?
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A: unanswerable


Problem: Madonna has sold more than 300 million records worldwide. The Guinness World Records acknowledged her as the best-selling female recording artist and the fourth best-selling act of all time, behind The Beatles, Elvis Presley, and Michael Jackson. According to the Recording Industry Association of America (RIAA), she is the best-selling female rock artist of the 20th century and the second top-selling female albums artist in the United States, with 64.5 million certified albums. Madonna is the most certified artist of all time in United Kingdom, with 45 awards from the British Phonographic Industry (BPI) as of April 2013. Billboard named Madonna as the top touring female artist of all time. She is also the highest grossing solo touring artist, with over $1.31 billion in concert gross, starting from the Blond Ambition World Tour; she first crossed a billion gross with The MDNA Tour. Overall, Madonna ranks third on all-time top-grossing Billboard Boxscore list, with just The Rolling Stones ($1.84 billion) and U2 ($1.67 billion) ahead of her. Madonna has been honored with 20 MTV Video Music Awards—the most for any artist—including the lifetime achievement Video Vanguard Award in 1986.
How much did Madonna make in all her concerts together?
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Answer: $1.31 billion


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The foundation has donated billions of dollars to help sufferers of AIDS, tuberculosis and malaria, protecting millions of children from death at the hands of preventable diseases. However, a 2007 investigation by The Los Angeles Times claimed there are three major unintended consequences with the foundation's allocation of aid. First, sub-Saharan Africa already suffered from a shortage of primary doctors before the arrival of the Gates Foundation, but "by pouring most contributions into the fight against such high-profile killers as AIDS, Gates grantees have increased the demand for specially trained, higher-paid clinicians, diverting staff from basic care" in sub-Saharan Africa. This "brain drain" adds to the existing doctor shortage and pulls away additional trained staff from children and those suffering from other common killers. Second, "the focus on a few diseases has shortchanged basic needs such as nutrition and transportation". Third, "Gates-funded vaccination programs have instructed caregivers to ignore – even discourage patients from discussing – ailments that the vaccinations cannot prevent".
Vaccinations programs encouraged what 
A: discourage patients from discussing – ailments that the vaccinations cannot prevent".


Context and question: Rendering software which cannot process a Unicode character appropriately often displays it as an open rectangle, or the Unicode "replacement character" (U+FFFD, �), to indicate the position of the unrecognized character. Some systems have made attempts to provide more information about such characters. The Apple's Last Resort font will display a substitute glyph indicating the Unicode range of the character, and the SIL International's Unicode Fallback font will display a box showing the hexadecimal scalar value of the character.
What does rendering software display when it can't process a Unicode character? 
Answer: open rectangle, or the Unicode "replacement character"


Question: After the war, Operation Glory was conducted from July to November 1954, to allow combatant countries to exchange their dead. The remains of 4,167 U.S. Army and U.S. Marine Corps dead were exchanged for 13,528 KPA and PVA dead, and 546 civilians dead in UN prisoner-of-war camps were delivered to the South Korean government. After Operation Glory, 416 Korean War unknown soldiers were buried in the National Memorial Cemetery of the Pacific (The Punchbowl), on the island of Oahu, Hawaii. Defense Prisoner of War/Missing Personnel Office (DPMO) records indicate that the PRC and the DPRK transmitted 1,394 names, of which 858 were correct. From 4,167 containers of returned remains, forensic examination identified 4,219 individuals. Of these, 2,944 were identified as American, and all but 416 were identified by name. From 1996 to 2006, the DPRK recovered 220 remains near the Sino-Korean border.
Is there an answer to this question: How many US service members were exchanged during this operation?

Answer: 4,167


It took about 20 years to build the city from 1911. Many elements of New Delhi architecture borrow from indigenous sources; however, they fit into a British Classical/Palladian tradition. The fact that there were any indigenous features in the design were due to the persistence and urging of both the Viceroy Lord Hardinge and historians like E.B. Havell.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What historian is partially responsible for the use of indigenous features in the architecture of New Delhi?
Ah, so..
E.B. Havell