The entire race took Henry 1hr:36min which is 96min. He has an average speed of 30km/hr means he's been traveling 0.5km/min
30km/hr > 30km/1hr >
30km/60min = 0.5km/min
since Henry took 96min to finish the race we multiply 0.5km/min with 96
0.5km/min*96min=48km
look it up hare
sorry if it's not what your looking for
For everyone 4 feet he drops, 1 second will pass. (for everyone 1 second that goes by, he will be 4 feet lower)
12/3=4