let the angle be x,
(x/360)* pi * 4^2 = 2 pi
x = 2 * 360 / 16 = 45
Either you are clairvoyant, or know what problem # this is... care to share what # out of what problem set it is?
nice comments mate.
I just used the whatever I know,
area of a sector = (unknown angle / 360 deg) * pi * (radius)^2
since radius is given and area of the shaded region is given as 2 * pi.
I substituted the values and got 45 deg.
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