Answer:
15.7 cm
Step-by-step explanation:
The length (s) of an arc of a circle of radius r with a central angle of θ radians is ...
s = rθ
Here, the radius is given as 7.9 cm, and the arc of interest is the supplement of 66.4°, so is ...
θ = π·(1 - 66.4/180) ≈ 1.9827 . . . . radians
Then the arc length is ...
s = (7.9 cm)·(1.9827) ≈ 15.7 cm