That's two questions.
The answer to the second question is: Yes.
The answer to the first question is:
Multiply 60 miles per hour by ' 1 ' a few times. Use fractions that have
the same thing on top and bottom, since those are always equal to ' 1 '.
Then cancel units if the same unit is on the top and the bottom.
Here's how it goes:
(60 mi/hr) x (5280 ft/mile) x (1hr/3600 sec) = (60 x 5280 / 3600) ft/sec = 88 ft/sec