Find the volume of a sphere whose diameter is 42 m.

Correct option is C

Given:

Diameter: 42m

Formula used: 

Volume of the sphere;

​$$V = \frac{4}{3} \pi r^3$$​​

Solution:

$$\text{Diameter} = 42 \, \text{m}, \quad r = \frac{\text{Diameter}}{2} = \frac{42}{2} = 21 \, \text{m}$$ 

Substitute (r = 21) into the formula:

​$$V = \frac{4}{3} \pi (21)^3$$ 

$$V = \frac{4}{3} \pi (9261) = \frac{4}{3} \times \frac{22}{7} \times 9261$$ 

$$V= 441\times22\times7$$ 

= $${38,808 \, \text{m}^3}$$ 

Thus the correct answer is (C)

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