<span>The exhibition was intended to give a preview, a glimpse of the future, of the possibilities. But not a fantastical or an improbable one but a future that is within our grasps. A future that we are actually reaching with these ideas and technologies that are in development and once mastered will change our lives immeasurably.</span>
Answer:
By using Gateway Arch as the symbol to represent United States expansion policy.
Explanation:
Gateway Arch, which is located in St. Louis Missouri, was designed by Error Saarinen in 1948 and its construction was completed in 1965, costing a whopping is $13million at the time.
It derived its name from "Gateway to west", a slogan used by the US during the westward expansion in the 19th century.
The artist used the Gateway Arch symbol to represent the a door to the western part of United States.