The area of a circle is increased by 22 cm2 when its radius is increased by 1 cm. The original radius of the circle is
3 cm
5 cm
7 cm
7 cm
The sum of all interior angles of a regular polygon is twice the sum of all its exterior angles. The number of sides of the polygon is
10
8
12
12
The height of a right prism with a square base is 15 cm. If the area of the total surfaces of the prism is 608 sq. cm. its volume is
910 cm3
920 cm3
960 cm3
960 cm3
If the diagonals of a rhombus are 8 and 6, then the square of its side is
25
55
64
64
A.
25
The volume of a solid hemisphere is 19404 cm3. Its total surface area is
4158 cm2
2858 cm2
1738 cm2
1738 cm2
If m and n are positive integers and (m - n) is an even number, then (m2 - n2) will be always divisible by
4
6
8
8
If a + b + c = 6, a2 + b2 + c2 = 14 and a3 + b3 + c3 = 36, then the value of abc is
3
6
9
9