Input: Article: The specifics of Paleo-Indian migration to and throughout the Americas, including the exact dates and routes traveled, provide the subject of ongoing research and discussion. According to archaeological and genetic evidence, North and South America were the last continents in the world with human habitation. During the Wisconsin glaciation, 50–17,000 years ago, falling sea levels allowed people to move across the land bridge of Beringia that joined Siberia to north west North America (Alaska). Alaska was a glacial refugia because it had low snowfall, allowing a small population to exist. The Laurentide Ice Sheet covered most of North America, blocking nomadic inhabitants and confining them to Alaska (East Beringia) for thousands of years.

Now answer this question: A small population could exist in Alaska because of it's lack of any significant what?

Output: snowfall

Input: Article: Political boundaries drawn by the British did not always reflect homogeneous ethnicities or religions, contributing to conflicts in formerly colonised areas. The British Empire was also responsible for large migrations of peoples. Millions left the British Isles, with the founding settler populations of the United States, Canada, Australia and New Zealand coming mainly from Britain and Ireland. Tensions remain between the white settler populations of these countries and their indigenous minorities, and between white settler minorities and indigenous majorities in South Africa and Zimbabwe. Settlers in Ireland from Great Britain have left their mark in the form of divided nationalist and unionist communities in Northern Ireland. Millions of people moved to and from British colonies, with large numbers of Indians emigrating to other parts of the empire, such as Malaysia and Fiji, and Chinese people to Malaysia, Singapore and the Caribbean. The demographics of Britain itself was changed after the Second World War owing to immigration to Britain from its former colonies.

Now answer this question: In which countries did the British Isles provide most of the founding settlers?

Output: the United States, Canada, Australia and New Zealand

Input: Article: New York City is supplied with drinking water by the protected Catskill Mountains watershed. As a result of the watershed's integrity and undisturbed natural water filtration system, New York is one of only four major cities in the United States the majority of whose drinking water is pure enough not to require purification by water treatment plants. The Croton Watershed north of the city is undergoing construction of a US$3.2 billion water purification plant to augment New York City's water supply by an estimated 290 million gallons daily, representing a greater than 20% addition to the city's current availability of water. The ongoing expansion of New York City Water Tunnel No. 3, an integral part of the New York City water supply system, is the largest capital construction project in the city's history.

Now answer this question: Who supplies NYC with drinkable water?

Output:
Catskill Mountains watershed