Angle BC is parallel to Angle DF, Angle DF is parallel to GH. What is the relationship between Angle BC and GH? Explain.

The answer is that BC and GF are parallel to each other.

Since BC and DF are parallel to each other, and DF and GH are parallel to each other, it's basically like three parallel lines beside each other

If angle BC is parallel to angle DF and angle DF itself to parallel to angle GH then angle GH is parallel to BC.