At 60 miles per hour, you need to calculate that into minutes or seconds. At 60 miles per hour multiplied by 1 hr/60 minutes gives you 1 mile per minute. This can be translated into 5280 feet per minute since 1 mile is 5280 feet. At 5280 feet per minute, one can multiple that by 1 minute/60 seconds to get 88 feet per second and then multiple that by 15 seconds to give you 1320 feet from the point you started.