If the radius of a circle is increased by 21%, then its area will increase by what percent?
1). 42 percent
2). 21 percent
3). 23.205 percent
4). 46.41 percent
2. The area of an equilateral triangle is 49√3 cm2. Find its side (in cm).
5. The surface area of two spheres are in the ratio 9 : 16. Their volumes will be in the ratio
7. The area of an equilateral triangle is $4\sqrt{3}$ sq.cm. Its perimeter is
8. Each edge of a regular tetrahedron is 3 cm,then its volume is
9. Total surface area of a cube is 486 sq cm, find sum of length of all its edges?