Answer:
320°
Explanation:
Part 1
The arc length is given by ...
s = rθ . . . . . r is the radius, θ is the central angle in radians
We want to find θ, so we can fill in the given values and divide by the coefficient of θ.
8π = 4.5θ
θ = 8π/4.5 = 16π/9 . . . radians
Since π radians = 180°, the degree measure of the angle is ...
θ = (16/9)180° = 320°
The measure of the angle subtended by the arc is 320°.
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Part 2
We might be able to help with the second part of the question, but you need to edit to put in the numbers and answer choices.