Final answer:
The length of the arc intercepted by a central angle can be found using the formula s = θr. Using the given values, the arc length is 21π centimeters.
Step-by-step explanation:
The formula to find the length of an arc on a circle of radius r intercepted by a central angle θ is given by:
arc length s = θr
In this case, the radius r is given as 12 centimeters and the central angle θ is given as 7π/4. Substituting these values into the formula, we get:
arc length s = 7π/4 * 12 = 21π centimeters