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Disintegration and Decomposition of rocks by chemical processes is called “Chemical weathering”. 

In this process secondary or new minerals are developed from the original minerals of the rocks. The rain water and atmospheric gases are the main agents of chemical weathering. It is vey common in humid regions. 

There are four types of chemical weathering process. They are;

• Oxidation: The rain water with oxygen reacts on rocks containing iron and produce oxides. This chemical reaction is known as “oxidation”. The common process of rusting of iron is an example of oxidation. 
• Carbonation: The rain water with carbon-di-oxide becomes a weak carbonic acid and it reacts with calcium carbonate or limestone to form calcium bicarbonate, which dissolves easily. This process is called “Carbonation”. It is very active in limestone regions. 
• Hydration: The rock minerals take up water the increased volume creates physical stress within the rock. As a result certain minerals like feldspar and gypsum are reduced into powder. This process is called “Hydration”. 
• Solution: The rain water is able to dissolve some of the soluble minerals, such as rock- salt, gypsum, potash. This process is called “Solution”.

Rock refers to the hard and resistant materials of the earth’s crust. But scientifically rock includes even soft and loose materials like chalk, clay, etc. So, rock refers to any solid materials, hard or soft of which the crust of the earth is formed. All rocks do not have the same chemical composition. But minerals have their own chemical compost in and physical prosperities. .The earth’s crust is made up of various types of rocks

Types of Rocks: Rocks can be classified into three major groups on the basis of their origin or mode of formation. They are:

A. Igneous rocks: The term Igneous is derived from the Latin word “Ignis”, means lire. Thus the igneous rocks are formed by the cooling and solidification of molten material which is called magma. Igneous rocks are also called primary rocks, because they were the firs to be formed. As they are the rocks from which all other types of rocks are derived, they are also called parent rocks.

Igneous rocks are commonly classified on the basis of mode of formation into two major types. 

i. Intrusive rocks 

ii. Extrusive rocks.

I. Intrusive rocks: The magma cannpt escape out to the earth’s surface, it cols slowly inside the earth’s crust and hardens into rock. This type of rock is known as Intrusive Igneous rock. E.g. Granite and dolerite. These rocks can be divided into two type’s a. Plutonic rocks and b. Hybabyssal rocks.

a. Plutonic rocks: The rocks which are formed due to cooling of magma at great depth inside the earth are called Plutonic igneous rocks.

b. Hybabyssal rocks: These are intermediate rocks between the extruded volcanic rocks and the deep plutonic rocks. They are formed due to cooling and solidification of magma in cracks, pores, crevices etc.

II. Extrusive rocks: Rocks formed by cooling and solidification of lava on the surface of the Earth is called extrusive igneous rocks. E.g. Basalt.

B. Sedimentary Rocks: These rocks which are formed due to aggregation and compactness of sediments are known as sedimentary. In other words, sedimentary rocks are formed bye day the deposition of sediments derived form older rocks, planets and animals remains by river, winds, glaciers etc and these sediments are hardened into rocks by pressure. As they are formed by the consolidation of sediments. They are called sedimentary rocks. They are also called stratified rocks,

a. Mechanically-formed rocks: The rock which have been formed form the accumulation of rock materials, derived form other rocks and have been cemented together are known as “ Mechanically formed rocks.” The mechanically formed rocks consist of sediments which have been carried and deposited by rivers, glaciers, winds or waves and cemented together with clay or line. On the basis of rock materials. These rocks can be divided into three main categories. They are: Rudaceous rocks, Arernaceous rocks and Argilious rocks.

b. Chemically formed rocks: The chemical often settle down and hardened to form rocks known as chemically formed rocks. For example: Gypsum and rock salt, running water dissolves and carries chemicals and where evaporation takes place, these chemicals are deposited at the mouth of springs, caves or caverns or in lakes. Rock salt and gypsum are formed form deposit of salt in strata on the beds of lakes.

c. Organically formed rocks: Organic rocks are formed form the remains of organisms, i.e. of animals and plants. Examples: coal, limestone etc. On the basis of lime and carbon content, organically formed rocks can be divided into two kinds, namely.

(i) Calcareous rocks: Calcareous rocks are formed mostly from the remains of living organisms. These rocks contain calcium carbonate or lime. They include limestoneand chalk. They are porous and soluble.

(ii) Carbonaceous rocks: These are formed due to the transformation of vegetative matter. Under the impact of heat and pressure the remains of plants are turned into hard layers. E.g. coal.

C. Metamorphic rocks: Rock which has been changes either in form or in composition without disintegration is called metamorphic rocks. These rocks are metamorphosed from igneous sedimentary rocks. Igneous and sedimentary rocks may undergo chemical and physical changes because of pressure and heat and form metamorphic rocks. The intense heat and pressure in the earth’s curst alters the composition and appearance of rocks completely or partially to produce a new type of rocks. In this manner metamorphic. rocks are formed. Marble, Diamond, Quartzite, Ruby, Emerald are the examples of metamorphic rock.

An Earthquake is a sudden vibration or oscillation in the Crust of the Earth. It is a form of energy of wave motion transmitted through the surface layer of the Earth. The place of origin of an Earthquake in the Earth’s crust is called ‘Focus’. The point on the Earth surface which is perpendicular to the focus, receiving seismic waves is called ‘Epicentre’.

Causes of Earthquake: On the basis of occurrence earthquakes can be classified into three types. They occur due to several causes such as tectonic forces, folding, faulting, volcanic eruptions landslides, avalanches, man-made factor.

Tectonic Earthquakes: These are caused due to folding, faulting and displacement of blocks of rocks in the Earth’s crust. They are highly intensive and destructive seismic activities.

Volcanic Earthquakes: These are associated with the volcanic activities and are usually caused at great depths. They are with low intensity and magnitude. The destruction and damage are slightly lesser than earthquakes caused by Tectonic forces.

c. Earthquakes caused by man-made factors: Over interaction of man underground nuclear explosion etc, are causing great change in the crustal formation leading to seismic activity. E.g. Koyna dam (India)-1967, Hoover dam (U.S.A)-1935, Mangladam (Pakistan). Effects of Earthquakes: Earthquakes cause violent disturbances and widespread damage and destruction, especially on the epicentre region.

• Earthquakes cause changes in the earth’s surface. Cracks and fissures develop in the earth’s crust. 
• Vibrations, caused by earthquakes, lead to landslides in mountainous regions, damming the rivers. 
• vertical or horizontal cracks are formed, and the land is elevated or lowered, forming lakes. 
• Deep cracks may be developed in dams after the earthquake. For instance, deep cracks were developed in the Koyna dam after the earthquake. 
• The beds of rivers may be raised by the earthquakes. For example, the bed of the river Brahmaputra was raised during the Assam earthquakes. 
• here is the greatest danger of falling of houses, roads railway lines factories, bridges, dams, aerodromes, and other man-made structures, resulting in loss of life and property. 
• The underground water system is disturbed.

An Earthquake is a sudden vibration or oscillation in the Crust of the Earth. It is a form of energy of wave motion transmitted through the surface layer of the Earth. The place of origin of an Earthquake in the Earth’s crust is called ‘Focus’. The point on the Earth surface which is perpendicular to the focus, receiving seismic waves is called ‘Epicentre’.

Causes of Earthquake: On the basis of occurrence earthquakes can be classified into three types. They occur due to several causes such as tectonic forces, folding, faulting, volcanic eruptions landslides, avalanches, man-made factor.

Tectonic Earthquakes: These are caused due to folding, faulting and displacement of blocks of rocks in the Earth’s crust. They are highly intensive and destructive seismic activities.

Volcanic Earthquakes: These are associated with the volcanic activities and are usually caused at great depths. They are with low intensity and magnitude. The destruction and damage are slightly lesser than earthquakes caused by Tectonic forces.

c. Earthquakes caused by man-made factors: Over interaction of man underground nuclear explosion etc, are causing great change in the crustal formation leading to seismic activity. E.g. 

Koyna dam (India)-1967, Hoover dam (U.S.A)-l 935, Mangladam (Pakistan). Effects of Earthquakes: Earthquakes cause violent disturbances and widespread damage and destruction, especially on the epicentre region.

• Earthquakes cause changes in the earth’s surface. Cracks and fissures develop in the earth’s crust. 
• Vibrations, caused by earthquakes, lead to landslides in mountainous regions, damming the rivers. 
• vertical or horizontal cracks are formed, and the land is elevated or lowered, forming lakes. 
• Deep cracks may be developed in dams after the earthquake. For instance, deep cracks were developed in the Koyna dam after the earthquake. 
• The beds of rivers may be raised by the earthquakes. For example, the bed of the river Brahmaputra was raised during the Assam earthquakes. 
• here is the greatest danger of falling of houses, roads railway lines factories, bridges, dams, aerodromes, and other man-made structures, resulting in loss of life and property. 
• The underground water system is disturbed.

There are three important region. 

1. Himalayan zone 

2. Western Ghats 

3. Southern Plateau.

The ancient people made attempts to determine the size of the Earth. About 2,000 years ago a Greek astronomer, Eratosthenes, who lived In Alexandria in Egypt succeeded in calculating the size of the earth almost accurately, according to him, the earth’s circumference at the equator was 41,140 kms. It was very close to the actual circumference of the earth, as known today.

The actual equatorial circumference of the earth is 40,076 km, where as the polar circumference is 40,006 km. The difference between the two is 70 km. The earth’s equatorial diameter is 12,757 km and the polar diameter is 12,714 km. The difference is 43 km. The geoids shape of the earth makes the circumference through the poles little less than that along the equator. The total surface area of the earth is 510. 9 million sq kms of the surface area, 71 % is covered by water mass and 29% is covered by landmass. The water mass is 361 million sq.kms and the land area is 149 million sq.kms. The land area is divided into seven continents and many island. The continents are Asia, Africa, and North America, South America, Antarctica, Europe and Australia.

The water area consist of five ocean, namely, the pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Antarctic ocean and the Arctic Ocean and many gulfs, bays and seas. The globe is divided into two hemispheres, namely the northern hemisphere and the southern hemisphere, by the equator. The northern hemisphere contains 2/3 of the land and the southern hemisphere contains 1/3 of the land. The zero degree meridians decide the globe into two hemispheres, namely, the eastern hemisphere and the western hemisphere.

Correct option is (1) The diameter of dispersed particles is much smaller than the wavelength of light used

The word Geography is derived from the two Greek word ‘Geo’ which means earth and Graphic which means writing or study. Thus literally Geography means writing or study about the earth. Geography not only deals with a description of the earth, but it also deals with its inhabitants. So, Geography is the study of the earth and its people. 

Cultural Geography, Historical Geography, Economic Geography, Agricultural Geography.

Geography is fundamentally a description of the earth. It deals with the varied natural or physical factors of environment, such as land forms, mountains water bodies, minerals, climate, soils, natural vegetation and plains.

Agumbe of Karnataka is ‘Mawsynram’ of South India’ 

The term drought is applied to an extended period when there is a shortage of water availability due to inadequate precipitation, excessive rate of evaporation and over utilization of water from the reservoirs other storages, including the ground water.

Godavari is the longest (1465km) and largest river of south India

The two major streams are Alakananda and Bhagirathi.

Indira point located at Great Nicobar Island.

Indira point located at Great Nicobar Island. 

The varied range of flora and fauna found within a specified geographic region is called ‘Biodiversity’ .

A volcano is an opening in the crust of the Earth through which heated materials consisting of gases, hot water, lava and fragments of rocks are ejected from the interior of the Earth.

It refers to the amount of dissolved solids in the ocean water. In other words. It means the amount of salt in the ocean water. ” 

 Let say density of solution is g/ml.

∵ 100 g of solution contain = 75g HCl

∴ 500g of solution contain = \(\frac{75 \times 500}{100} = 75 \times 5g\; HCl\)

∴ Number of moles of HCl = \(\frac{75\times 5}{36.5} = 10.27\, mol\)

∴ Initial concentration of HCl solution = \(\frac{10.27}{500}\times 1000= 20.55 M\)

Let say, After dilution the volume of solution become V

then,

\(V \times 0.1 = 20.55 \times 500\)

\(V = \frac{20.55\times 500}{0.1}\)

\(= 102750 \,ml\)

\(V = 102.75 \,l\)

Chemical energy stored within organic molecules such as sugars and fats is transferred and transformed through a series of cellular chemical reactions into energy within molecules of ATP.

The steps to implement bag of words algorithm are as follows: 

1. Text Normalisation: Collect data and pre-process it 

2. Create Dictionary: Make a list of all the unique words occurring in the corpus. (Vocabulary) 

3. Create document vectors: For each document in the corpus, find out how many times the word from the unique list of words has occurred. 

4. Create document vectors for all the documents.

Projection used to transform 3D platform to a 2D platform.

The process of calculating one's position, especially at sea, by estimating the direction and distance travelled rather than by using landmarks or astronomical observations.

Mathematics is the study of numbers, shapes, quantities, and patterns. Mathematics is the ‘queen of all sciences’ and its presence is there in all the subjects. It acts as the basis and structure of other subjects. Some points to remember:

• On the basis of intuition, hypothesis are made in mathematics.
• A mathematics statement can be conditional. For example, a figure can not be said a 'rectangle' its opposite sides are not parallel and equal, and all angles are inclined at 90 degrees.
• Mathematics is not about theorems only. It contains other symbols, statements like axioms, and calculation.
• A person with good arithmetic computation does not guarantees that he is good in mathematics. Maybe he can lack in geometry or algebra.

Hence, a mathematics statement can be conditional.

Given:

Let salary of P and Q be Rs.20a and Rs.21a respectively.

Calculation:

⇒ 21a - 20a = 2000

⇒ a = 2000

The monthly salary of P and Q is Rs.40000 and Rs.42000 respectively.

⇒ Expenditure of Q = 42000 - 14000 = Rs.28000

Then,

⇒ (Expenditure of P) : 28000 = 5 : 7

⇒ Expenditure of P = 28000 × 5/7 = Rs.20000

⇒ Savings of P = 40000 - 20000 = Rs.20000

Required ratio = 20000 : 14000 = 10 : 7

∴ the correct answer is 10 : 7

4, 4, 6, 12, 30, ? 

Above series follows given below pattern:

4 × 1 = 4

4 × 1.5 = 6

6 × 2 = 12

12 × 2.5 = 30

30 × 3 = 90

∴ The missing number in the series 4, 4, 6, 12, 30, ? is 90

Mathematical reasoning is a topic of mathematics which deals with truthfulness and falsehood of a statement. A statement is a sentence which is either true or false, but can not be both at the same time. There are certain terms that are frequently used in mathematical reasoning:

• Inverse: The conditional statement “~p → ~q” is called the inverse of the conditional statement “ p → q ”, where (~ p) and (~ q) means 'not p' and 'not q' respectively. For example, if 'n is not even, n² is not even' is the inverse of 'if n is even, n² is even.'
• Converse: The conditional statement “q → p” is called the converse of the conditional statement “ p → q ”. Example, 'if n2 is even, then n is even' is the converse of 'If n is even, then n2 is even'.
• Contrapositive: The statement “(~ q) → (~ p)” is called the contrapositive of the statement p → q. For example, 'If n2 is not even, then n is not even' is contrapositive of 'If n is even, then n2 is even'

Hence, we conclude that the above relation is of contraposition.

A triangle is a two-dimensional figure which has three sides and the sum of whose angles is 180 degrees.

There are certain conditions for a figure to be triangle as stated below:

• There are three sides of a triangle, which is necessary. Having three sides does not guarantee that the figure is a triangle.
• The sum of lengths of two sides should always be greater than the third side.
• The difference of length of two sides should always be less than the third side.

Hence, we conclude that for a given figure to be a triangle, the condition that it is a union of three segments is ​a necessary but not a sufficient condition.

Assessment is a process of collecting relevant information on student learning. It is one of the crucial components of the teaching-learning process. 

The Assessment Strategies that can be used to encourage interdisciplinary in Mathematics as stated below.

• Students' justification of their responses should be an important basis of assessment because it says a lot about students understanding.
• Giving the same task to students will not let a teacher assess its students individual differences plays a crucial role in students learning.
• Their incorrect answers should be observed to understand their thinking.
• To check how well a student understands math's, his vocabulary of mathematics should be assessed.
• The differences among these integrative strategies are rooted in the goals of the interdisciplinary curriculum and the purposes of the discipline driving the integration.

Hence, Students' justification of their responses should be an important basis of assessment.

Formative Evaluation: Evaluation is called formative evaluation when its purpose is to modify the educational proposals and to make them more relevant to the individual student’s needs. When the evaluation of the learning activity is based on the formative approach, it must be as analytical as possible. Formative evaluation is a tool for providing feedback to the teaching/learning process. This type of instruction motivates the teacher and the student and reinforces learning by providing feedback to both of them. The process of ‘self-assessment’ serves the purpose of formative evaluation. Formative assessment is concerned with identifying learner weakness in attainment with a view to helping the learner and the teacher overcome/remedy those.​ Characteristics of the formative assessment:

• Builds on students’ prior knowledge and experience in designing what is taught.
• Is conducted at regular intervals on an informal basis.
• Is diagnostic and remedial. It should be noted that since evaluation happens at regular interval, hence a teacher focuses on the identification of the minor learning difficulties of a student.
• Ensures provision for effective feedback.
• Provides a platform for the active involvement of students in their own learning.
• Provides feedback enabling teachers to adjust their classroom interaction strategies to the emerging needs of the students.
• Encourages intrinsic motivation and self-esteem of students, both of which have crucial influences on learning performance.
• Recognizes the need for students to be able to assess themselves and understand how to improve.
• Incorporates varied learning styles to decide how and what to teach.
• Encourages students to understand the criteria that will be used to judge their work.
• Offers an opportunity for students to improve their work after they get feedback.
• Helps students to support their peer group and vice-versa.

Hence, we conclude that the purpose of formative evaluation in Mathematics is the identification of minor learning difficulties of students.