The range of a linear function can be found by evaluating the end-points, namely [-2,2] (assuming [-2,2] interval notation meaning from -2 to 2 was intended). f(-2)=-6-12=-18 f(2)=6-12=-6 so the range of function f(x)=3x-12 for the domain [-2,2] is [-18,-6].
If the domain is actually {-2,2}, meaning only x=-2 and x=2, then the range would be {-18,-6}, i.e. exactly two points.
Answer: I just finished this unit in geometry and to find the measurements of inscribed angle ( angle looks ABC inside a circle) it is half of the central angle (AOC). So the angle of ABC is 1/2 AOC. So your answer will be ABC = 29°