The water tank

The water tank has the shape of a sphere with a radius of 2 m. How many liters of water will fit in the tank? How many kilograms of paint do we need to paint the tank, if we paint with 1 kg of paint 10 m²?

Correct answer:

V =  33510.3216 l
m =  5.0265 kg

Step-by-step explanation:

$$\begin{gathered} r=2\text{m} \\ {V}_1=\frac{4}{3}\cdot \pi \cdot r^3=\frac{4}{3}\cdot 3.1416\cdot 2^3\doteq 33.5103{\text{m}}^3 \\ V=V_1\to \text{l}=V_1\cdot 1000\text{l}=33.5103\cdot 1000\text{l}=33510.322\text{l}=33510.3216\text{l}=3.351\cdot 10^4\text{l} \end{gathered}$$

$$\begin{gathered} S=4\pi \cdot r^2=4\cdot 3.1416\cdot 2^2\doteq 50.2655{\text{m}}^2 \\ h=10{\text{m}}^2\text{/kg} \\ m=S/h=50.2655/10=5.0265\text{kg} \end{gathered}$$

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