I attached the image related to the question.
Answers:
arc FG is 67°
m∠ECF=67°
Step-by-step explanation:
Part (a):
We are given that chord DE is congruent to chord FG.
This congruency means that arc DE is congruent to arc FG.
From the drawing, we can see that measure arc DE = 67°
Therefore:
measure arc FG = 67°
Part (b):
We are given that chord DE is congruent to chord EF.
This congruency means that angles DCE and ECF are congruent.
From the drawing, we can see that measure angle DCE = 67°
Therefore:
measure angle ECF = 67°
Hope this helps :)