Answer: Option A. -> To find how many tiles are needed to cover the floor of a room.
:
A
Area is the total space occupied by any2D shape.
$\therefore$ To know the number of tiles required to cover a floor, we need to find the total space of the floor or the area of the floor first and then will have to divide this area by the area of one tile.
To find the amount of water in the lake we need to find the capacity or volume occupied by the lake.
To find the cost of fencing a ground we need to calculate the perimeter of the ground.
To find the amount of paint in a container we need to find the capacity of the container which is its volume. So we need to calculate its volume.

Answer: Option C. -> 10 cm
:
C
Given: Volume of the cube: $1000c{m}^3$
Volume of a cube = $Sid{e}^3$
$\Rightarrow$ $Sid{e}^3=1000c{m}^3$
$\Rightarrow$ $Side=10cm$
Therefore, the length of the side will be 10 cm.

Answer: Option D. -> 64 cm3
:
D
Given: Length of each side = 4 cm
Volume of a cube = $Sid{e}^3$
= $(4cm{)}^3$
= $64c{m}^3$
Therefore, volume of the given cube is $64c{m}^3$.

Answer: Option C. -> 16 cm2
:
C
Given: Perimeter= 16 cm
Perimter of a square = 4 $\times$Side
$\Rightarrow$ 16 cm = 4 $\times$Side
$\Rightarrow$ Side $=\frac{16}{4}=4cm$
Area of a square = Side $\times$ Side
$\Rightarrow$ Area of the square $=4cm\times 4cm=16c{m}^2$

Answer: Option D. -> 4 cm
:
D
Given : Perimeter of the given figure= 15 cm
Let the length of the third side be x.
Perimeter of a figure = Sum of lengths of itssides = AB + BC + AC
$\Rightarrow$ 15 cm = 6 cm + 5 cm + x
$\Rightarrow$ 15 cm = 11 cm + x
$\Rightarrow$x = 15 cm - 11 cm
$\Rightarrow$x = 4 cm
Therefore, the third side is 4 cm long.

Answer: Option A. -> Sum of length of all the sides.
:
A
Perimeter of an irregular polygonis the sum of length of all the sides.
For the irregular polygon given below,
the perimeter is 4 cm + 9cm + 10 cm + 8 cm which is equal to 31 cm.

Answer: Option A. -> 11 Cm2
Area of 1 square = 1 cm2 Number of squares in the given figure = 11∴ Area of figure = 11 × 1 = 11 cm2

Answer: Option A. -> 10 cm3
:
A
Given: Volume of each block is $1c{m}^3$
There are 10 blocks in the given figure.
$\Rightarrow$ Volume of the object $=10\times 1c{m}^3=10c{m}^3$

Answer: Option C. -> length × breadth × height
:
C

Volume of a rectangular prism (cuboid) = length $\times$ breadth $\times$ height

Answer: Option D. -> 4 units
:
D
Given: Perimeter = Area (Numerically)
Perimeter of square $=4\times Side$
Area of square $=Side\times Side$
Perimeter = Area (Given)
$\Rightarrow$ $4\times Side$ $=Side\times Side$
$\Rightarrow$$Side=4units$
$\therefore$ If the Perimeter and area of a square areequal, then the side is 4 units long.