A ball of lead 4 cm in diameter is covered with gold. If the volume of the gold and lead are equal, then the thickness of gold [given ] is approximately.

• 5.038 m

• 5.190 cm

• 1.038 cm

• 1.038 cm

A large solid sphere is melted and moulded to form identical right circular cones with base radius and height same as the radius of the sphere. One of these cones is melted and moulded to form a smaller solid sphere. Then the ratio of the surface area of the smaller to the surface area of the larger sphere is

Two sides of a plot measuring 32 m and 24 m and the angle between them is a perfect right angle. The other two sides measure 25 m each and the other three angles are not right angles. The area of the plot in m² is

• 768

• 534

• 696.5

• 696.5

a and b are two sides of adjacent to the right angle of a right-angled and p is the perpendicular drawn to the hypotenuse from the opposite vertex. Then p² is equal to

A conical cup is filled with ice cream. The ice-cream forms a hemispherical shape on its open top. The height of the hemispherical part is 7 cm. The radius of the hemispherical part equals the height of the cone. Then the volume of the ice-cream is 

• 1078 cubic cm

• 1708 cubic cm

• 7108 cubic cm

• 7108 cubic cm

16.

A is the centre of a circle whose radius is 8 and B is the centre of a circle whose diameter is 8. If these two two circles touch externally, then the area of the circle with diameter AB is

• 
• 
• 
• 

If  then the value of  is

• 0

• 2

• 1

• 1

If ab + bc + ca = 0, then the value of  is

• 0

• 1

• 3

• 3

If  then the value of  is

• 1

• 2

• 
• 

If , then  is

• 0

• 
• 
•