Answer:
∠72°.
Step-by-step explanation:
If a circle has a circumference of 20 and an arc with a length of 4, we can simply set up a ratio to determine the angle of the arc in degrees:

Cross multiply:

Divide both sides by '20':
x = 72°.
Therefore, the measure of the central angle of the arc is ∠72°.
I believe you would take 127.5 and divide it by 8.5, try that and see if that works, hope this helps!
Answer:
21, 24, 27, 30, 33, 36, 39.
Step-by-step explanation:
Wait, this is simplified because there are no common terms.