A pillar 42cm in diameter is 15 m high. How much material (in cm³) was used to construct it?$$(Take \pi = \frac{22}{7})$$​​

Correct option is A

Given:

Diameter of pillar = 42 cm

Height of pillar = 15m

Formula Used:

Volume of cylinder = $$\pi \times (r^2) \times h$$​​

Solution:

Here radius of cylinder = $$\frac{42}{2} = 21cm$$​​

Height of pillar in cm = $$15 \times 100 = 1500cm$$​​

Hence, 

Volume of cylinder = $$\pi \times ((21)^2) \times 1500$$​​

​$$= \frac{22}{7} \times 441 \times 1500$$​​

​$$= 22 \times 63 \times 1500$$​

​$$=20,79,000 \ cm^3$$​​

​$$= 2.079 \times 10^6 cm^3$$