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Paul asks his friend to record himself skateboarding off a ramp. The ramp has a slope of 12\frac{1}{2} while the ramp itself is 2 meters high. Paul's friend is standing 4 meters away on a platform so that it is level with the top of the ramp with the camera pointed at the ramp. The angular elevation of the camera, θ(t)\theta(t) , starts at 0 and increases with time so that the camera follows the trajectory of Paul. When Paul is at a horizontal distance of xx from the ramp, the vertical distance he has is measured by f(x)f(x) from the top of the ramp.

Assuming the Paul is moving horizontally at a speed of 5 m/s when he jumps off the ramp, how quickly is his friend rotating the camera in order to follow his trajectory as he leaves the ramp? Note that f(0)=0f(0) = 0 and that f(0)=13f'(0) = \frac{1}{3} .
(Diagram not to scale)
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