Problem: Antenna (radio):

Current circulating in one antenna generally induces a voltage across the feedpoint of nearby antennas or antenna elements. The mathematics presented below are useful in analyzing the electrical behaviour of antenna arrays, where the properties of the individual array elements (such as half wave dipoles) are already known. If those elements were widely separated and driven in a certain amplitude and phase, then each would act independently as that element is known to. However, because of the mutual interaction between their electric and magnetic fields due to proximity, the currents in each element are not simply a function of the applied voltage (according to its driving point impedance), but depend on the currents in the other nearby elements. Note that this now is a near field phenomenon which could not be properly accounted for using the Friis transmission equation for instance.

Where are the indiviual array elements known?
---
A: antenna arrays

Problem: Adult contemporary music:

After 1965, differences between the Hot 100 chart and the Easy Listening chart became more pronounced. Better reflecting what middle of the road stations were actually playing, the composition of the chart changed dramatically. As rock music continued to harden, there was much less crossover between the Hot 100 and Easy Listening chart than there had been in the early half of the 1960s. Roger Miller, Barbra Streisand and Bobby Vinton were among the chart's most popular performers.

In what year did the Easy Listening and Hot 100 charts begin to diverge?
---
A: 1965

Problem: Hard rock:

Established acts benefited from the new commercial climate, with Whitesnake's self-titled album (1987) selling over 17 million copies, outperforming anything in Coverdale's or Deep Purple's catalogue before or since. It featured the rock anthem "Here I Go Again '87" as one of 4 UK top 20 singles. The follow-up Slip of the Tongue (1989) went platinum, but according to critics Steve Erlwine and Greg Prato, "it was a considerable disappointment after the across-the-board success of Whitesnake". Aerosmith's comeback album Permanent Vacation (1987) would begin a decade long revival of their popularity. Crazy Nights (1987) by Kiss was the band's highest charting release in the US since 1979 and the highest of their career in the UK. Motley Crue with Girls, Girls, Girls (1987) continued their commercial success and Def Leppard with Hysteria (1987) hit their commercial peak, the latter producing seven hit singles (a record for a hard rock act). Guns N' Roses released the best-selling debut of all time, Appetite for Destruction (1987). With a "grittier" and "rawer" sound than most glam metal, it produced three top 10 hits, including the number one "Sweet Child O' Mine". Some of the glam rock bands that formed in the mid-1980s, such as White Lion and Cinderella experienced their biggest success during this period with their respective albums Pride (1987) and Long Cold Winter (1988) both going multi-platinum and launching a series of hit singles. In the last years of the decade, the most notable successes were New Jersey (1988) by Bon Jovi, OU812 (1988) by Van Halen, Open Up and Say... Ahh! (1988) by Poison, Pump (1989) by Aerosmith, and Motley Crue's most commercially successful album Dr. Feelgood (1989). New Jersey spawned five Top 10 singles, a record for a hard rock act. In 1988 from 25 June to 5 November, the number one spot on the Billboard 200 album chart was held by a hard rock album for 18 out of 20 consecutive weeks; the albums were OU812, Hysteria, Appetite for Destruction, and New Jersey. A final wave of glam rock bands arrived in the late 1980s, and experienced success with multi-platinum albums and hit singles from 1989 until the early 1990s, among them Extreme, Warrant Slaughter and FireHouse. Skid Row also released their eponymous debut (1989), reaching number six on the Billboard 200, but they were to be one of the last major bands that emerged in the glam rock era.

What Guns N Roses album was the second best selling debut of all time?
---
A: Appetite for Destruction

Problem: Financial crisis of 2007%E2%80%9308:

A 2000 United States Department of the Treasury study of lending trends for 305 cities from 1993 to 1998 showed that $467 billion of mortgage lending was made by Community Reinvestment Act (CRA)-covered lenders into low and mid level income (LMI) borrowers and neighborhoods, representing 10% of all U.S. mortgage lending during the period. The majority of these were prime loans. Sub-prime loans made by CRA-covered institutions constituted a 3% market share of LMI loans in 1998, but in the run-up to the crisis, fully 25% of all sub-prime lending occurred at CRA-covered institutions and another 25% of sub-prime loans had some connection with CRA. In addition, an analysis by the Federal Reserve Bank of Dallas in 2009, however, concluded that the CRA was not responsible for the mortgage loan crisis, pointing out that CRA rules have been in place since 1995 whereas the poor lending emerged only a decade later. Furthermore, most sub-prime loans were not made to the LMI borrowers targeted by the CRA, especially in the years 20052006 leading up to the crisis. Nor did it find any evidence that lending under the CRA rules increased delinquency rates or that the CRA indirectly influenced independent mortgage lenders to ramp up sub-prime lending.

What was the value of mortgage lending made by Community Reinvestment Act covered lenders to low and mid level income borrowers and neighborhoods from 1993-1998?
---
A:
$467 billion