In the above figure, ∠aob = 80°. what does ∠acb equal? a. 10° b. 160° c. 80° d. 40°

Half of AOB,
that is,
80/2 = 40°

You can find it by multiplying the areas it show u

Period is the time it takes for one “cycle” to complete. in the parent sine function, period is 2*pi since sin(0) = 0, sin(pi/2) = 1, sin(pi) = 0, sin(3pi/2) = -1, and sin(2pi) = 0. at that point, the sequence repeats itself. i’m not sure if your graph is similar to the sine function since you didn’t provide a picture, but you can find the period by looking at a graph.