If a solid cube of side 16 cm is cut into eight identical cubes. The side of each cube is:

1. 2 cm

2. 4 cm

3. 6 cm

4. 8 cm

The diameters of two solid spheres are in the ratio 5 : 7. The ratio between areas of their curved surfaces is :

1. 5 : 7

2. 7 : 5

3. 49 : 25

4. 25 : 49

Statement 1: Each side of a cuboid is doubled, its total surface area is also doubled.

Statement 2: The surface area of resulting cuboid is 2 x 2 x 2 times the original area.

1. Both the statements are true.

2. Both the statements are false.

3. Statement 1 is true, and statement 2 is false.

4. Statement 1 is false, and statement 2 is true.

Assertion (A): The radius of a hemisphere increases from r cm to 2r cm. The ratio between the surface area of the original hemisphere and the resulting hemisphere is 1 : 4.

Reason (R): Surface area of the first case = πr² + 2πr²

Surface area of the second case = π(2r)² + 2π(2r)²

1. A is true, but R is false.

2. A is false, but R is true.

3. Both A and R are true, and R is the correct reason for A.

4. Both A and R are true, and R is the incorrect reason for A.