Answer: (4) inches per minute
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Explanation:
Check out the attached image below. I've marked up your diagram such that I've canceled the proper units. Any cancelation happens when we divide one unit over another. Take note of the color coding.
The miles units cancel out (in red), the hours units cancel (blue), and the feet units cancel (green). We're left with inches over minutes, which leads to the final units being "inches per minute".
