The formula for linear velocity of a person riding on the wheel is


V =  ft/hour,


where n is the number of revolution of the wheel per hour (= (60 min/12 min) = 5 revolutions per hour.)


Substitute the given values  to get

V = 5*3.14*175 ft/hour = 2747.5 ft/hour =   = 0.52 miles per hour.