I just took a Geometry test, and I am relatively sure I did well on it. I am positive I got the first three questions right

This proof is really bugging me because Geometry is my best subject. However, I am stumped on this problem. I created an image of the diagram on Imageshack and am sharing it with you. I hope some of you can help!
Here is the link and a picture of the same thing (just in case the link doesn't work):

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This is a 2-column proof.
-DwightKSchrute