Left figure: area $=\frac{1}{2}\cdot \pi \cdot \mathrm{1,5}\cdot \sqrt{{\mathrm{1,5}}^2+3^2}+\frac{1}{2}\cdot \pi \cdot {\mathrm{1,5}}^2\approx \mathrm{11,44}$ .
Middle figure: area $=\frac{1}{4}\cdot 4\pi \cdot {\mathrm{1,5}}^2+2\cdot \frac{1}{2}\cdot \pi \cdot {\mathrm{1,5}}^2=\mathrm{4,5}\pi \approx \mathrm{14,14}$ .
Right figure: area $=2\cdot (\pi \cdot \mathrm{1,5}\cdot \sqrt{{\mathrm{1,5}}^2+{\mathrm{1,25}}^2}-\pi \cdot \mathrm{0,5}\cdot \sqrt{{\mathrm{0,5}}^2+{\mathrm{0,75}}^2})+2\cdot \pi \cdot {\mathrm{1,5}}^2\approx \mathrm{25,64}$ .

Area $=2\cdot \frac{1}{2}\cdot 8\cdot \sqrt{34}+2\cdot \frac{1}{2}\cdot (12+6)\cdot \sqrt{41}=8\sqrt{34}+18\sqrt{41}$.

Area $=5\cdot \frac{1}{2}\cdot 4\cdot \sqrt{4^2-2^2}+5\cdot \frac{1}{2}\cdot 4\cdot \frac{2}{tan\left(36\right)}\approx \mathrm{62,17}$.

area $=\pi \cdot \mathrm{1,5}\cdot \sqrt{{\mathrm{1,5}}^2+1^2}+\pi \cdot 2\cdot \sqrt{{12}^2+2^2}-\pi \cdot \mathrm{1,5}\cdot \sqrt{{\mathrm{1,5}}^2+9^2)}\approx \mathrm{43,13}$.

area $=\frac{3}{4}\cdot \pi \cdot {119}^2-\frac{3}{4}\cdot \pi \cdot {19}^2\approx \mathrm{32515,5}$ cm².

The figure consists of two regular octagons and $16$ equilateral triangles with edges $4$ cm long.
area $=2\cdot 8\cdot \frac{1}{2}\cdot 4\cdot \frac{2}{tan(\mathrm{22,5}°)}+16\cdot \frac{1}{2}\cdot 4\cdot \sqrt{4^2-2^2}\approx \mathrm{265,36}$ .

area $=4\pi \cdot 4^2-2\cdot \pi \cdot 4\cdot (4-\sqrt{4^2-3^2})+2\pi \cdot 3\cdot 3\approx \mathrm{223,6}$ m².