The roof

The roof has the shape of a spherical canopy with a base diameter of 8 m and a height of 2 m, calculate the area of the foil with which the roof is covered, when we calculate 13% for waste and residues.

Correct result:

S =  56.8 m²

Solution:

$$\begin{gathered} d=8\text{ m } \\ v=2\text{ m } \\ \rho =d\mathrm{/}2=8\mathrm{/}2=4\text{ m } \\ {S}_1=2\pi \cdot \rho \cdot v=2\cdot 3.1416\cdot 4\cdot 2\doteq 50.2655{\text{m}}^2 \\ q=13\mathrm{\%}=1+{\displaystyle \frac{13}{100}}=1.13 \\ S=q\cdot S_1=1.13\cdot 50.2655=56.8{\text{m}}^2 \end{gathered}$$

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