Thirty years ago, police would check a highway for speeders by sending a helicopter up in the air and observing the time it would take for a car was observed to take 7.2 seconds to travel this distance. how much time did it take the car to travel the distance in hours?

You apparently skipped some words and didn't copy them into the question. Fortunately, those words were part of the "red herring" section ... the part that only distracts you, and is completely unnecessary in order to answer the question.

The actual question here is:  "What fraction of an hour is  7.2  seconds ?"

(7.2 sec) x (1 hour/3,600 sec)  =  7.2 / 3600  =  0.002 hour .