If the diameter of the base of a cone is 70 cm and its curved surface area is 4070 cm², then what will be its volume (in cm³)? $$(use\pi = \frac{22}{7} )$$​​

Correct option is C

Diameter = 70 and radius = 70/2 = 35 cm

Curved Surface Area = 4070 $$cm^2$$

$$\frac{22}{7} \times 35\times l = 4070$$

l= 37 cm 

h = $$\sqrt{l^2-r^2 } =\sqrt{ 37^2 -35^2} = 12 cm$$

Volume of cone = $$\frac{1}{3} \pi r^2 h = \frac{1}{3} \times\frac{22}{7}\times35^2\times 12 = 15400 cm^3$$​​