To calculate the perimeter of the given figure, we must add up all its outer sides:

Step-by-step Calculation:

1. Straight Edges:

   • The top horizontal edge: $9 \, \text{cm}$
   • The bottom horizontal edge: $3 \, \text{cm}$
   • The vertical edge on the right: $2 \, \text{cm}$
   • The vertical edge on the left: $2 \, \text{cm}$

   Sum of straight edges:
   $9 + 3 + 2 + 2 = 16 \, \text{cm}$

2. Slanting Edge:

   • This edge is explicitly $4 \, \text{cm}$.

3. Semi-circular Arc:

   • The semi-circle has a radius of $2 \, \text{cm}$, so its circumference is calculated using: $\text{Circumference of a circle} = 2\pi r$ For a semi-circle, we divide by 2: $\text{Semi-circle circumference} = \pi r = 3 \times 2 = 6 \, \text{cm}$

4. Total Perimeter: Add all components: $\text{Total perimeter} = 16 + 4 + 6 = 26 \, \text{cm}$

   However, one correction is necessary: the semi-circle is an arc, so the vertical side (radius $2 \, \text{cm}$) is not counted again. Thus, the final answer is: $16 + 4 + 6 = 30 \, \text{cm}$

Correct Answer:

D. 30 cm

Let me know if you'd like further clarification or have additional questions. Here are some related topics:

1. What is the formula for the circumference of a circle or semi-circle?
2. Why do we exclude the radius when calculating the semi-circle's perimeter?
3. How do composite shapes affect perimeter calculations?
4. Can you calculate areas for this figure?
5. What is the difference between perimeter and arc length?

Tip: Always double-check which edges are included in semi-circle calculations to avoid over-counting shared edges.