13. 10-14 14.I can't see the whole graph, so you need to do it yourself. Add up everyone's age and divide by the amount of people on the graph. That will give you the average.
To get this answer in meters per second, we first have to convert each of the terms into either meters or seconds. We can do that by multiplying by unit rates.
21 km * 1000 = 21,000 meters
1 hour * 3600 = 3,600 seconds
40 minutes * 60 = 2,400 seconds
Now we divide the meters by the total number of seconds to get the rate.
