Answer:
c.
Step-by-step explanation:
That is the only answer choice that makes the most sense.
±10 = √100; in this case, they want the non-negative value, so it is 10.
You could use so many for example 4, 10, 57, 5729, any number above 4 would work since that plus 8 would be greater than 11
8/13 = 0.6153
y = cos-1(0.6153)
y = 52.0
I'm not totally sure if this is what you mean or if this is.
y = cos(8/13) = 0.9999 which to the nearest tenth is 1.0