Final answer:
The principal angle for θ = -200 degrees is found by adding 360 degrees to make it positive, resulting in 160°.
Step-by-step explanation:
The principal angle is the smallest positive angle that is coterminal with a given angle. When an angle is given as θ = -200 degrees, to find its principal angle, we add or subtract multiples of 360 degrees until the result is a positive angle less than 360 degrees.
In this case, we can add 360 degrees to -200 degrees to find the principal angle:
-200° + 360° = 160°
Therefore, the principal angle when θ is -200 degrees is 160°, which corresponds to option b).