Answer:
Bradbury´s opening uses the literary device of personification by granting a human trait (the capacity to tremble because of weakness) to a non-living thing (the sign on the wall). This sentence also works as a foreshadowing element, as it sets the mood for something going wrong.
Explanation:
Furthermore, it relates to a later metaphor about time being "a film run backward." In the end, the protagonist finds himself trembling because of his weakness, his incapacity to go through the film of time without causing trouble.
Area in Math is what is inside of an outline/shape. For example, if you are given an outline of a rectangle, you can calculate the area by multiplying one short side with one long side. The total number gives you the amount of space inside the rectangle.
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