7. The six semicircles present in the figure on the side all have a radius of $1 \mathrm{~cm}$. How many $\mathrm{cm}^{2}$ is the area of the shaded region?
(A) $8+3 \pi / 4$
(D) $6+3 \pi / 2$
(B) $9+\pi / 2$
(C) $9+\pi / 3$
(E) $10+\pi / 6$
(7) The correct answer is $(D)$.

We can partition the region as indicated by the dashed lines in the figure. The total area of the two rectangles is then $6 \mathrm{~cm}^{2}$, while that of the circular sectors is $\frac{3}{2} \pi \mathrm{cm}^{2}$. Problem proposed by Carmelo Di Stefano.

![](https://cdn.mathpix.com/cropped/2024_04_17_d5ce41e6c6aa67789846g-1.jpg?height=238&width=458&top_left_y=2426&top_left_x=1343)