In the figure, AB||CD||EF. Which of the following statements is true?
A a + b =180°
B b + c = 180°
C c + d =180°
D a + b + c = 360°
In the figure, AB||CD||EF. Which of the following statements is true?
A a + b =180°
B b + c = 180°
C c + d =180°
D a + b + c = 360°