Answer: C) increase from 45 degrees to 50 degrees
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Step-by-step explanation:
Let's calculate the angle B based off the arcs CDF and GHJ
B = (far arc - near arc)/2
B = (arc CDF - arc GHJ)/2
B = (130 - 40)/2
B = 90/2
B = 45
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Now let's change GHJ to 30 degrees, while keeping the other arc the same.
B = (far arc - near arc)/2
B = (arc CDF - arc GHJ)/2
B = (130 - 30)/2
B = 100/2
B = 50
Angle B has increased from 45 degrees to 50 degrees.