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The undergraduates have a number of traditions: Painting The Rock (originally a fountain donated by the Class of 1902) is a way to advertise, for example, campus organizations, events in Greek life, student groups, and university-wide events. Dance Marathon, a 30-hour philanthropic event, has raised more than 13 million dollars in its history for various children's charities. Primal Scream is held at 9 p.m. on the Sunday before finals week every quarter; students lean out of windows or gather in courtyards and scream. Armadillo Day, or, more popularly, Dillo Day, a day of music and food, is held on Northwestern's Lakefill every Spring on the weekend after Memorial Day. And in one of the University's newer traditions, every year during freshman orientation, known as Wildcat Welcome, freshmen and transfer students pass through Weber Arch to the loud huzzahs of upperclassmen and the music of the University Marching Band.
 What is the popular name for Southwestern's traditional Armadillo Day?
A: unanswerable

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The Melbourne rail network has its origins in privately built lines from the 1850s gold rush era, and today the suburban network consists of 209 suburban stations on 16 lines which radiate from the City Loop, a partially underground metro section of the network beneath the Central Business District (Hoddle Grid). Flinders Street Station is Melbourne's busiest railway station, and was the world's busiest passenger station in 1926. It remains a prominent Melbourne landmark and meeting place. The city has rail connections with regional Victorian cities, as well as direct interstate rail services to Sydney and Adelaide and beyond which depart from Melbourne's other major rail terminus, Southern Cross Station in Spencer Street. In the 2013–2014 financial year, the Melbourne rail network recorded 232.0 million passenger trips, the highest in its history. Many rail lines, along with dedicated lines and rail yards are also used for freight. The Overland to Adelaide departs Southern Cross twice a week, while the XPT to Sydney departs twice a day.
Which rail station is Melbourne's busiest?
A: Flinders Street Station

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Midtown Raleigh is a residential and commercial area just North of the I-440 Beltline and is part of North Raleigh. It is roughly framed by Glenwood/Creedmoor Road to the West, Wake Forest Road to the East, and Millbrook Road to the North. It includes shopping centers such as North Hills and Crabtree Valley Mall. It also includes North Hills Park and part of the Raleigh Greenway System. The term was coined by the Greater Raleigh Chamber of Commerce, developer John Kane and planning director Mitchell Silver. The News & Observer newspaper started using the term for marketing purposes only. The Midtown Raleigh Alliance was founded on July 25, 2011 as a way for community leaders to promote the area.
When was the Midtown Raleigh Alliance formed?
A: July 25, 2011

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Another aspect of anti-aircraft defence was the use of barrage balloons to act as physical obstacle initially to bomber aircraft over cities and later for ground attack aircraft over the Normandy invasion fleets. The balloon, a simple blimp tethered to the ground, worked in two ways. Firstly, it and the steel cable were a danger to any aircraft that tried to fly among them. Secondly, to avoid the balloons, bombers had to fly at a higher altitude, which was more favorable for the guns. Barrage balloons were limited in application, and had minimal success at bringing down aircraft, being largely immobile and passive defences.
What did pilots have to do to avoid the barrage balloons?
A:
fly at a higher altitude