EnviroMission[?] is planning to build one in Australia. If built, it will become the tallest structure in the world, with a height of one kilometer.
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... the city the population is spread out with 27.2% under the age of 18, 8.7% from 18 to 24, 29.5% from 25 to 44, 21.0% from 45 to 64, and 13.5% who are 65 years of age or ...