Bedrock is hard but absolutely breakable, and most of the high-rise buildings are anchored into the bedrock with structures called "foundations". It is a deposit of solid rock that is typically buried beneath the soil alongside other broken materials. Bedrock is made up of igneous, sedimentary, or metamorphic rock, and it often serves as the parent material for soil.

Explain the fact why soil is found at the topmost layer.

Soil is one of the most important natural resources. Soil is formed from the rocks. It provides anchorage to the plants and supplies water and nutrients. It is a home to many organisms. Soil is essential for agriculture and agriculture provides food, clothing and shelter for all. Soil is thus an inseparable part of our life. 

a) If rocks had not broken down, life would not have developed on the earth. Why? 

b) Discuss the factors that affect soil formation.

A sample of soil is taken in a funnel lined with filter paper. The funnel is placed over a measuring cylinder. At $2:00 \mathrm{pm}$, Raksha starts to pour $200 \mathrm{mL}$ of water slowly on the soil. She finishes pouring all the water by $2:10 \mathrm{pm}$. Given here are the readings of water levels in the measuring cylinder at different times.

Look at the table and answer the questions below:

1. How much water (in $\mathrm{mL}$) was absorbed by the soil?

2. What is the percolation rate? Give your answer in $\mathrm{mL}/\min$.

3. Which type of soil is the sample? Sandy soil, clayey soil or loamy soil. Give reasons for your answer.

Priya poured a litre of water into a pot with a hole filled with garden soil. After a while, she collected the water dropping from the hole below and measured it in a beaker. The beaker reading showed as $450 \mathrm{mL}$. She was shocked and asked her teacher what had happened to the rest of the water. The teacher informed that soil has a water-holding capacity. She also explained to her the various properties of soil, as well as how to calculate the percentage of water absorption of soil. After she explained everything, the teacher asks her to calculate the percentage of water absorption of the soil if there is $1.5 \mathrm{kg}$ of soil in the pot. (Assume the density of water as $1 \mathrm{g}/\mathrm{mL}$). Also, give a reason why soil absorbs water.

Akash and Drithi's family planned to travel to their hometown by car. While travelling, they saw the various farms on both sides of the highway. They noticed that different crops are planted in different regions. They asked their parents why didn't they find same type of crops growing everywhere?

Sara and Rajiv were making soil art and craft for their school project. Their grandma suggested that the soil from the bank of their village pond would be good for creating such models. Why was grandma's suggestion useful?

Once on a great sunny day, soil and trees were discussing with each other.

Said Soil to Tree, "Aren't you grateful to me?
I hold your roots firmly, so deep in the ground".
"No, no," said Tree.
"Surely you can see that the facts are actually the other way around. My roots keep you safe all night and all day.
If it wasn't for me, you'd soon be washed away".

"Stop fighting, you two" said an Owl sitting on the tree. "You both help each other, and you both help me."

Mention two ways in which Soil and Tree help each other. Also comment on the statement made by Owl "You both help me."  

Darjeeling is the northernmost district of the state of West Bengal in eastern India in the foothills of the Himalayas, popularly known as the 'Queen of the Hills'. Ramu lives in Darjeeling and does farming there. What method of farming should he use to prevent soil from being eroded?

Amit and his friends are having fun playing with soil in the field. Amit gathered some soil from the ground in a tiny bucket and brought it into his house. He then emptied the bucket in his compound. All the kids looked at the various things other than soil, like chocolate pieces, glass fragments, etc. When Amit's mother saw them playing with all these things, she warned them not to touch these soil pollutants as they can harm them and also contains fertilisers and pesticides. She also stated said, "Prolonged usage of pesticides is undesirable." Amit was taken aback by her response because he was aware that pesticides and fertilisers were used to increase crop yield.

a) "Prolonged use of pesticides is undesirable". Comment on this statement given by Amit's mother.

b) How is soil pollution caused? Discuss some measures of how soil pollution can be controlled.