Answer:
radian
Explanation:
We know that angle for a full circle is 2
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In the given figure shape is semicircle
hence,
angle for semicircle will be half of angle of full circle
thus, angle for given figure = half of angle for a full circle = 1/2 * 2
=
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Thus, answer is
radian
alternatively, we also know that angle for a straight line is 180 degrees
and 180 degrees is same as
radian.