The curved surface area of a right circular cone of height 15 cm and base diameter 16 cm is

(a)

60\(\pi\) cm²

(b)

68\(\pi\) cm²

(c)

120\(\pi\) cm²

(d)

136\(\pi\) cm²

If two solid hemispheres of same base radius r units are joined together along their bases, then curved surface area of this new solid is

(a)

4\(\pi\)r² sq.units

(b)

6\(\pi\)r² sq.units

(c)

3\(\pi\)r² sq.units

(d)

8\(\pi\)r² sq.units

The height of a right circular cone whose radius is 5 cm and slant height is 13 cm will be

(a)

12 cm

(b)

10 cm

(c)

13 cm

(d)

5 cm

If the radius of the base of a right circular cylinder is halved keeping the same height, then the ratio of the volume of the cylinder thus obtained to the volume of original cylinder is

(a)

1:2

(b)

1:4

(c)

1:6

(d)

1:8

The total surface area of a cylinder whose radius is \(\frac{1}{3}\)of its height is

(a)

\(\frac { 9\pi { h }^{ 2 } }{ 8 } \) sq.units

(b)

24\(\pi\)h² sq.units

(c)

\(\frac { 8\pi { h }^{ 2 } }{ 9 } \) sq.units

(d)

\(\frac { 56\pi { h }^{ 2 } }{ 9 } \) sq.units