question: One Queensbridge and Australia 108 are two buildings currently under construction aiming to be the tallest building in which city?
answer: Melbourne
context: Title: List of tallest buildings in Pennsylvania
  Passage: This lists the tallest buildings in Pennsylvania, over 120 meters (400 feet), ranked by height.  The tallest building in Pennsylvania is the 58-story Comcast Center located in Philadelphia, which at 975 feet (297 meters) is currently the 20th-tallest building in the United States.  It was topped out on June 18, 2007, to become the tallest building in Philadelphia and the state.  The currently under construction Comcast Technology Center in Philadelphia, which will rise 60 stories and 1121 feet tall, will be the tallest building in Philadelphia and the state of Pennsylvania upon its completion in 2018.  It will also be the 9th tallest building in the United States.  All of the buildings over 120 meters are in Philadelphia and Pittsburgh; 30 are in Philadelphia and 16 are in Pittsburgh.
  Title: U.S. Bank Tower (Los Angeles)
  Passage: U.S. Bank Tower, formerly Library Tower and First Interstate Bank World Center, is a 1018 ft skyscraper at 633 West Fifth Street in downtown Los Angeles, California.  It is the third tallest building in California, the second tallest building in LA, the fifteenth tallest in the United States, the third tallest west of the Mississippi River after the Salesforce Tower and the Wilshire Grand Center, and the 92nd tallest building in the world, after being surpassed by the Wilshire Grand Center.  Because local building codes required all high-rise buildings to have a helipad, it was known as the tallest building in the world with a roof-top heliport from its completion in 1989 to 2004 when Taipei 101 opened.  It is also the third tallest building in a major active seismic region; its structure was designed to resist an earthquake of 8.3 on the Richter scale.  It consists of 73 stories above ground and two parking levels below ground.  Construction began in 1987 with completion in 1989.  The building was designed by Henry N. Cobb of the architectural firm Pei Cobb Freed & Partners and cost $350 million to build.  It is one of the most recognizable buildings in Los Angeles, and often appears in establishing shots for the city in films and television programs.
  Title: List of tallest buildings in Omaha, Nebraska
  Passage: The tallest buildings in Omaha, Nebraska include towers for Woodmen of the World and the First National Bank of Omaha.  Omaha's tallest building is the 634 ft (193 m), 45-story First National Bank Tower.  Completed in 1969, the 478 ft (146 m), 30-story tall Woodmen Tower was the tallest until the construction of the First National Bank Tower.  While most of the city's tallest buildings are located in Downtown Omaha, several are located in Midtown Omaha.  These include the 22-story, 320 ft (98 m) Masonic Manor, currently the third tallest building in the city, and the 285 ft (87 m), 14-story Mutual of Omaha Building.  The University of Nebraska Medical Center is located in midtown and among its rapidly expanding campus is the 230 ft Lied Transplant Center.  There was also a proposal to build a 373 ft (114 m) Wallstreet Tower Omaha on the site of the old Union Pacific Headquarters.  If the tower was completed, it would have been the city's third tallest building, however plans were eventually scrapped for the idea.
  Title: One Queensbridge
  Passage: One Queensbridge (or Crown Queensbridge) is an approved mixed–used supertall skyscraper to be located in the Southbank precinct of Melbourne, Australia.  When built, the skyscraper will become the tallest building in Melbourne, surpassing the height of Australia 108, and the tallest building in Australia, eclipsing the height of Q1.  In addition to being the tallest, the development is one of the biggest single–building projects in Australia, encompassing 300376 sqm of floor area.
  Title: Australia 108
  Passage: Australia 108 (previously 70 Southbank Boulevard) is a residential supertall skyscraper currently under construction in the Southbank precinct of Melbourne, Victoria, Australia.  When completed, it will become the tallest building in Australia by roof height, surpassing the Eureka Tower, and the second-tallest building in Australia by full height, surpassed by Q1.  The project consists of a 317 m apartment building with 1,105 apartments over 100 floors.  Construction commenced in 2015, with completion expected in 2020.
citations: Australia 108 One Queensbridge