Part (a)
The radius is r = 42 because OA = 42.
The circumference, aka distance around the circle, is
C = 2*pi*r
C = 2*(22/7)*42
C = 264
We're told that arc AB is 110 mm which is 110/264 = 5/12 of the full distance around the circle.
So we'll apply 5/12 to the full rotation 360 to get (5/12)*360 = 150
Answer: 150 degrees
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Part (b)
Compute the area of the full circle
A = pi*r^2
A = (22/7)*(42)^2
A = 5544
Then take 5/12 of this because we only want 5/12 of the full circle area (to get the area of the shaded pizza slice)
(5/12)*(5544) = 2310
Answer: 2310 square mm
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Side note: Both answers are approximate because pi = 22/7 is approximate.
