4.5mi/h. ft/sec tell me how to do this and give me answers with work

There are 5,280 feet in every mile so you would do:

4.5 x 5280 = 23,760 ft.

Since there are 3,600 seconds in every hour, you would do:

1 x 3600 = 3,600 sec.

So, the answer is:

23,760 ft/3,600 sec.

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