One kilometer is 1000 meters. One hour is 60 minutes, or six segments of 10 minutes each. If you can walk 1000 meters in 10 minutes, you can walk 6000 in an hour (that is REALLY fast, by the way)
One field is 25 + 45 + 25 + 45 = 140 feet Second field is 40 + 60 + 40 + 60 = 200 feet. Therefore, all together, the two fields are 340 feet in perimeter together