This is from GMATPrep.
Point O is the center of the semicircle and point points B, C and D lie on the semicircle. If the length of line segment AB = OC, what is the degree measure of angle BAO?
(1) angle COD = 60 degrees
(2) angle BCO = 40 degrees
The answer is D. I don't see how you can get the answer wither either of those statements alone.