A semicircle is exactly half a circle, so take the formula for circumference (*C* = 2*πr*) and divide by 2. Since *r* = 2, you end up with (2*π*(2))/2 = 2*π*. That covers the curved part.

You know the straight part has a length of 4 because the radius of the semicircle is 2.

4 + 2*π* is your answer.

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