Below here is a cricket ball and its cross-section. The diameter of the cricket ball is $7.2 \mathrm{cm}$.

Estimate the area of leather required to cover the cricket ball.

Below is a small cuboidal fish tank of dimensions $12 \mathrm{cm}\times 15 \mathrm{cm}\times 20 \mathrm{cm}$, partially filled with water. The level of water in the fish tank is $16 \mathrm{cm}$.

The fish tank is then kept in a different orientation as shown in the figure on the right side.

The height of the water in the fish tank is now is _____ $\mathrm{cm}$. (Give the answer correct up to one decimal place)

A welcome drink is served to the $100$ guests at a party. Each guest will get an equal portion of the drink in a cup as shown below.

According to the given measurement, the minimum quantity of the welcome drink required to serve all the guests once is _____ litres. (Write the answer up to one decimal)

Shown below is a cylindrical tank of height $1.96 \mathrm{m}$ and diameter $1 \mathrm{m}$. An inlet pipe of diameter $6 \mathrm{cm}$ and an outlet pipe of diameter $4 \mathrm{cm}$ are attached to the tank. The water is flowing into the water tank at a speed of $12 \mathrm{m}/\mathrm{minute}$ and it flows out at a speed of $6 \mathrm{m}/\mathrm{minute}$.

What is the volume of the water required to get the tank completely filled without spillage?

Due to the incessant rains the height of the field $100 \mathrm{m} \times 50 \mathrm{m}$had reduced drastically. It was then decided to dig a pit of $10 \mathrm{m}$ length and $5 \mathrm{m}$ depth as shown in the figure and spread it out evenly on the remaining part of the field.

What is the rise in the level of the remaining field?

The circumference of the spherical shaped coconut below is $37.052 \mathrm{cm}.$ The thickness of the shell including the edible part is $2 \mathrm{cm}.$

Estimate the amount of coconut water inside it, if it constitutes $60\%$ of its inner volume.

Which of these is the closest estimate of the amount of coconut water in the coconut?

Shyam is assigned a project for which he needs to make an electromagnet. To make an electromagnet a copper wire with diameter $3 \mathrm{mm}$ is wound to cover the curved surface area of the iron core cylinder, whose length is $12 \mathrm{cm}$ and diameter is $6 \mathrm{cm}$.

What is mass of the copper wire if its density of copper is $8.9 \mathrm{g}/\mathrm{cc}$ ?

Below is the picture of an open well $42 \mathrm{ft}$ deep and diameter $28 \mathrm{ft}$. The well needs to be plastered, and $50 \mathrm{kg}$ cement is required to plaster $300 {\mathrm{ft}}^2$. 

How much cement is required to plaster the wall of the well from top to bottom?