A right circular cone of largest volume is cut out from a solid wooden hemisphere. The remaining material is what percentage of the volume of the original hemisphere?

What is the area ( in cm² ) of the circumcircle of a triangle whose sides are 6 cm , 8 cm and 10 cm respectively ? 

The curved surface area of cylindrical pillar is $$ {264 m^{2}}$$ and its volume is $$ {924 m^{3}}$$. Find the ratio of its diameter to its height.

The diameter of a circle is equal to the perimeter of a square whose area is 3136 sq cm. What is the circumference of the circle?

In a triangle, ABC, P and Q are points on AB and AC, respectively, such that AP = 1 cm, PB = 3 cm, AQ = 1.5 cm, and CQ = 45 cm. If the area of ΔAPQ is 12 $${{cm^2}}$$, then find the area of BPQC.

If the height and the radius of the base of a cone are both doubled, the volume of the cone becomes _______ of its previous volume.