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The Skyscraper Challenge
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Inject a chemical glue to make the soil hard
You're on the right track.

 Inject a chemical glue to make the soil hard = Caution

In the 1970s, engineers had to strengthen the weak, sandy soil beneath the world's fifth and sixth tallest buildings -- the twin towers of the World Trade Center in New York City -- with a special chemical process. Unfortunately, chemical "glue" is an expensive process -- too expensive for your budget. Luckily, there is a cheaper method.

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Try again!

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