There are exactly π radians in a semicircle. there are exactly π radians in a full circle. there are approximately radians in a full circle. 2π radians is equivalent to degrees.

The correct option is there are exactly π radians in a semicircle.

We know that the length of an arc in radians L = rθ where

For a semi-circle, l = πr

So, πr = rθ

θ = π

So, the angle subtented by the semi-circle is π radians.

Now for a full circle, l = circumference of the circle = 2πr.

So, 2πr = rθ

θ = 2π

So, the angle subtented by the circle is 2π radians.

So, the correct option is there are exactly π radians in a semicircle.

Learn more about circle here:

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pi radians in a semicircle (half circle)

2pi radians in a full circle.

2pi = 2*3.14 = 6.28 approximately, so there are approximately 6.28 radians in a half circle.

2pi radians is equivalent to 360 degrees.