Input: Article: Throughout the 19th century, Philadelphia had a variety of industries and businesses, the largest being textiles. Major corporations in the 19th and early 20th centuries included the Baldwin Locomotive Works, William Cramp and Sons Ship and Engine Building Company, and the Pennsylvania Railroad. Industry, along with the U.S. Centennial, was celebrated in 1876 with the Centennial Exposition, the first official World's Fair in the United States. Immigrants, mostly Irish and German, settled in Philadelphia and the surrounding districts. The rise in population of the surrounding districts helped lead to the Act of Consolidation of 1854, which extended the city limits of Philadelphia from the 2 square miles of present-day Center City to the roughly 130 square miles of Philadelphia County.

Now answer this question: What was Philadelphia's biggest industry during the 19th century?

Output: textiles

Input: Article: In surveys made in Europe and the United States, green is the color most commonly associated with nature, life, health, youth, spring, hope and envy. In Europe and the U.S. green is sometimes associated with death (green has several seemingly contrary associations), sickness, or the devil, but in China its associations are very positive, as the symbol of fertility and happiness. In the Middle Ages and Renaissance, when the color of clothing showed the owner's social status, green was worn by merchants, bankers and the gentry, while red was the color of the nobility. The Mona Lisa by Leonardo da Vinci wears green, showing she is not from a noble family; the benches in the British House of Commons are green, while those in the House of Lords are red. Green is also the traditional color of safety and permission; a green light means go ahead, a green card permits permanent residence in the United States. It is the most important color in Islam. It was the color of the banner of Muhammad, and is found in the flags of nearly all Islamic countries, and represents the lush vegetation of Paradise. It is also often associated with the culture of Gaelic Ireland, and is a color of the flag of Ireland. Because of its association with nature, it is the color of the environmental movement. Political groups advocating environmental protection and social justice describe themselves as part of the Green movement, some naming themselves Green parties. This has led to similar campaigns in advertising, as companies have sold green, or environmentally friendly, products.

Now answer this question: Why is green the color of the environmental movement?

Output: its association with nature

Input: Article: In 1948, Eisenhower became President of Columbia University, an Ivy League university in New York City. The assignment was described as not being a good fit in either direction. During that year Eisenhower's memoir, Crusade in Europe, was published. Critics regarded it as one of the finest U.S. military memoirs, and it was a major financial success as well. Eisenhower's profit on the book was substantially aided by an unprecedented ruling by the U.S. Department of the Treasury that Eisenhower was not a professional writer, but rather, marketing the lifetime asset of his experiences, and thus he only had to pay capital gains tax on his $635,000 advance instead of the much higher personal tax rate. This ruling saved Eisenhower about $400,000.

Now answer this question: What group of schools did Columbia University belong to?

Output:
Ivy League