Sakshi drew a rangoli design for a competition as shown below:

Circles C₁, C₂, C₃ and C₄ have a common centre P.

The radius of circle C₁ = 6 cm.

The table given below shows the radii of the circles in terms of the radius of circle C₁.

Radius of circle	Radius in terms of circle C1
C2	2×
C3	2.5×
C4	3.5×

(i) The circumference of circle C₂ is :

(a) 12π cm
(b) 24π cm
(c) 15π cm
(d) 20π cm

(ii) The area enclosed between C₁ and C₂ and also between C₃ and C₄ has been painted.

What area of the rangoli has been painted ?

(a) 85π cm²
(b) 108π cm²
(c) 324π cm²
(d) 846π cm²

(i) Given,

Radius of circle C₁ = 6 cm.

Radius of circle C₂ = 2 × 6 = 12 cm.

Circumference of circle = 2πr

= 2π × 12

= 24π cm.

Hence, Option (b) is the correct option.

(ii) Given,

Radius of circle C₁ = 6 cm.

Radius of circle C₂ = 2 × 6 = 12 cm.

Radius of circle C₃ = 2.5 × 6 = 15 cm.

Radius of circle C₄ = 3.5 × 6 = 21 cm.

Area of ring = π(R² - r²)

Calculating the area between C₁ and C₂,

Area = π(12² - 6²)

= π(144 - 36)

= 108π cm².

Calculating the area between C₃ and C₄,

Area = π(21² - 15²)

= π(441 - 225)

= 216π cm².

Total area painted = 108π + 216π = 324π cm².

Hence, Option (c) is the correct option.