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Typical American families did not fare as well, nor did those "wealthy-but-not wealthiest" families just beneath the pyramid's top. On the other hand, half of the poorest families did not have wealth declines at all during the crisis. The Federal Reserve surveyed 4,000 households between 2007 and 2009, and found that the total wealth of 63 percent of all Americans declined in that period. 77 percent of the richest families had a decrease in total wealth, while only 50 percent of those on the bottom of the pyramid suffered a decrease.
How many families at the bottom of the pyramid had a decrease in total wealth between 2007 and 2009?
A: 50

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Desktop computers and laptops are commonly infected with malware either to gather passwords or financial account information, or to construct a botnet to attack another target. Smart phones, tablet computers, smart watches, and other mobile devices such as Quantified Self devices like activity trackers have also become targets and many of these have sensors such as cameras, microphones, GPS receivers, compasses, and accelerometers which could be exploited, and may collect personal information, including sensitive health information. Wifi, Bluetooth, and cell phone network on any of these devices could be used as attack vectors, and sensors might be remotely activated after a successful breach.
How are Quantified Self Devices breached?
A: unanswerable

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Philadelphia Gas Works (PGW), overseen by the Pennsylvania Public Utility Commission, is the nation's largest municipally owned natural gas utility. It serves over 500,000 homes and businesses in the Philadelphia area. Founded in 1836, the company came under city ownership in 1987 and has been providing the majority of gas distributed within city limits. In 2014, the Philadelphia City Council refused to conduct hearings on a $1.86 billion sale of PGW, part of a two-year effort that was proposed by the mayor. The refusal led to the prospective buyer terminating its offer.
When was PGW founded?
A: 1836

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Blues rock acts that pioneered the sound included Cream, The Jimi Hendrix Experience, and The Jeff Beck Group. Cream, in songs like "I Feel Free" (1966) combined blues rock with pop and psychedelia, particularly in the riffs and guitar solos of Eric Clapton. Jimi Hendrix produced a form of blues-influenced psychedelic rock, which combined elements of jazz, blues and rock and roll. From 1967 Jeff Beck brought lead guitar to new heights of technical virtuosity and moved blues rock in the direction of heavy rock with his band, The Jeff Beck Group. Dave Davies of The Kinks, Keith Richards of The Rolling Stones, Pete Townshend of The Who, Hendrix, Clapton and Beck all pioneered the use of new guitar effects like phasing, feedback and distortion. The Beatles began producing songs in the new hard rock style beginning with the White Album in 1968 and, with the track "Helter Skelter", attempted to create a greater level of noise than the Who. Stephen Thomas Erlewine of AllMusic has described the "proto-metal roar" of "Helter Skelter," while Ian MacDonald argued that "their attempts at emulating the heavy style were without exception embarrassing."
Keith Richards is the guitarist of what band?
A:
The Rolling Stones