Answer
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Work Step by Step
If a $180{}^\circ $ rotation of a line occurs, the direction of the line reverses.
Therefore, the statement, “My opinion about art museums took a $180{}^\circ $ turn after visiting the San Francisco Museum of Modern Art,” means that “My opinion about art museums was reversed after I visited the San Francisco Museum of Modern Art.”
For example: “Due to the blackout, the project was not saved and I have to turn $360{}^\circ $ to finish the project” means that “Due to the project not being saved, I have to start again to finish the project.” This is because, when a line rotates $360{}^\circ $ , it comes back to the initial position.
