The well

The well has the shape of a cylinder with a diameter of 2 m. From ground level to water level are 4 meters, and the water depth in the well is 6 m. How many m³ of soil did they dig when digging a well? How many liters of water is in the well?

Correct answer:

a =  31.4159 m³
b =  18850 l

Step-by-step explanation:

$$\begin{gathered} D=2\text{m} \\ {h}_1=4\text{m} \\ {h}_2=6\text{m} \\ r=D/2=2/2=1\text{m} \\ S=\pi \cdot r^2=3.1416\cdot 1^2\doteq 3.1416{\text{m}}^2 \\ a=S\cdot (h_1+h_2)=3.1416\cdot (4+6)=31.4159{\text{m}}^3 \end{gathered}$$

$$\begin{gathered} B=S\cdot h_2=3.1416\cdot 6\doteq 18.8496{\text{m}}^3 \\ b=B\to \text{l}=B\cdot 1000\text{l}=18.8496\cdot 1000\text{l}=18850\text{l}=18850\text{l} \end{gathered}$$

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