Answer:
At first glance, the author's purpose appears to be an informative one. We can assume he is going to teach us about important innovations to building designs, or architecture. He uses images and illustrations to clarify his ideas. He also bolded and set apart various technical terms so we don't miss them. Overall, the entire article follows the rhetorical strategy of extended definition as it defines and provides examples of these innovations.
Step-by-step explanation:
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