Final answer:
The angle's measure in radians in terms of the arc length s traveled along a Ferris wheel, assuming a unit circle, is represented by the expression πs. Therefore, the correct answer is d.
Step-by-step explanation:
The question asks for an expression to represent the measure of an angle in radians in terms of the arc length s traveled along the circumference of a Ferris wheel. By definition, the angle θ in radians is the ratio of the arc length s to the radius r of the circle, that is θ = em>s/r.
If there's no given radius, and assuming a unit circle (where r = 1) for simplicity, the angle θ is directly equal to the arc length. Therefore, the correct expression from the given options would be d. πs, where π represents the mathematical constant pi (approximately 3.14159).