This is Giancoli Answers with Mr. Dychko. Time is distance divided by speed so we have 5000 kilometers to go from New York to California divided by 10 kilometers an hour which we'll assume is the running speed here and so that's gonna work out to 500 hours and let's multiply that by 1 day for every 8 hours 8 hours of running you know, you have to sleep or at least take rest for the rest of the day and that means it would take about 60 days if you were to run about 8 hours per day to get across the US.
your answers do not match the answers in the back of the book. it seems they were looking for the 500h. answer alone.
Yes, and the question does ask "how many hours..." I've added the number of hours to the quick answer.
I'm glad it was helpful!