Input: Article: 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. Mötley Crüe 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 début 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 Mötley Crüe'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 début (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.

Now answer this question: What Guns N Roses album was the second best selling debut of all time?

Output: Appetite for Destruction

Input: Article: Its knowledge and uses spread from China through the Middle East to medieval Europe in the 13th century, where the first water powered paper mills were built. Because of paper's introduction to the West through the city of Baghdad, it was first called bagdatikos. In the 19th century, industrial manufacture greatly lowered its cost, enabling mass exchange of information and contributing to significant cultural shifts. In 1844, the Canadian inventor Charles Fenerty and the German F. G. Keller independently developed processes for pulping wood fibres.

Now answer this question: In which century did the process become much cheaper than before?

Output: 19th

Input: Article: Crevasses can form in several different ways. Transverse crevasses are transverse to flow and form where steeper slopes cause a glacier to accelerate. Longitudinal crevasses form semi-parallel to flow where a glacier expands laterally. Marginal crevasses form from the edge of the glacier, due to the reduction in speed caused by friction of the valley walls. Marginal crevasses are usually largely transverse to flow. Moving glacier ice can sometimes separate from stagnant ice above, forming a bergschrund. Bergschrunds resemble crevasses but are singular features at a glacier's margins.

Now answer this question: Where do transverse crevasses form?

Output:
where steeper slopes cause a glacier to accelerate