What is the arc length of arc cd in the circle below?

circle a is shown with a radius labeled 6 feet and a central angle marked 30 degrees.

3.14 feet
4.88 feet
6.98 feet
11.78 feet

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap