For a semicircle, perimeter = curved arc + diameter.<br><br>Curved arc = \(\frac{1}{2} \times 2\pi r = \pi r\).<br><br>Perimeter = \(\pi r + 2r = r(\pi + 2)\).<br><br>From the figure, radius \(r = 10.5\) cm. With \(\pi = \frac{22}{7}\):<br>\(10.5 \times (\frac{22}{7} + 2) = 10.5 \times \frac{36}{7} = 54\) cm.<br><br>Final Answer: 54 cm