smc

Note that the half the circumference of a circle with diameter $d$ is $\frac{\pi \ast d}{2}$. Let's call the diameter of the circle D. Dividing the circle's diameter into n parts means that each semicircle has diameter $\frac{D}{n}$, and thus each semicircle measures $\frac{D\ast pi}{n\ast 2}$. The total sum of those is $n\ast \frac{D\ast pi}{n\ast 2}=\frac{D\ast pi}{2}$, and since that is the exact expression for the semi-circumference of the original circle, the answer is $\boxed{\text{equal to the semi-circumference of the original circle}}$.