Tree mesh

The farm provided around 150 fruit trees with a trunk diameter of 2 dm with mesh to protect them from wild animals. The mesh was placed so that it was 9 cm away from the trunk. How many regular meters of mesh were needed?

Final Answer:

n =  179.1 bm

Step-by-step explanation:

$$\begin{gathered} D=2/10=\frac{1}{5}=0.2 \\ r=D/2=0.2/2=\frac{1}{10}=0.1 \\ o=2\pi \cdot (r+9/100)=2\cdot 3.1416\cdot (0.1+9/100)\doteq 1.1938 \\ n=150\cdot o=150\cdot 1.1938=179.1\text{bm} \end{gathered}$$

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