In one revolution of the wheel, a point on the edge travels a distance equal to the circumference of the wheel.
The wheel has radius 1 ft, so its circumference is 2π (1 ft) = 2π ft.
Then the point has a linear speed of
(1/4 rev/s) * (2π ft/rev) = 2π/4 ft/s = π/2 ft/s
