In the diagram, A, B, D, F, and G lie on a vertical line, \triangle B C D is right-angled at C, and \triangle D E F is rightangled at E. Also, \angle A B C=x^{\circ}, \angle C D E=80^{\circ}, and \angle E F G=y^{\circ}. What is the value of x+y ?
Answer Choices
A. 250
B. 260
C. 270
D. 280
E. 290