A hemisphere and a cone have equal bases. If their heights are also equal, then the ratio of their curved surfaces will be
1). 1:2
2). 2:1
3). $1:\sqrt{2}$
4). $\sqrt{2}:1$
1. The area (in sq. cm.) of the largest circle that can be drawn inside a square of side 28 cm. is :
5. What is the altitude of an equilateral triangle whose side is 12√3 cm?
9. What is the perimeter of the sector whose central angle is 60° and radius of the circle is 21 cm?
10. If the circumference of a circle is reduced by 50%. its area will be reduced by