Convert the ft/min speed into miles/hour: 
3520 feet ... 1 mile ..... 60 minutes ... 3520 x 60 miles 
-------------- x ------------- x ---------------- = --------------- 
1 minute ... 5280 feet .... 1 hour .......... 5280 hours 
= (3520 * 60) / 5280 
= 40 miles/hour 
Answer: 
The bison is 10 miles per hour faster than a deer.