It is reciprocal . refractive index of air wrt water is 1.0/1.33 = 0.752

In direct variation we do as follows-:

Let the height of the pole be x

6m=4m
x=50m

6/4=x/50. (cross multiply)
50*6=x*4
50*6/4=x
25*3=x
x=75

Means the flag pole height is of 75m.

=6x²-7x-3
=6x²+2x-9x-3
=2x(3x+1)-3(3x+1)
=(2x-3)(3x+1)
⇒2x-3=0                                    or                            ⇒3x+1=0
⇒x=3/2                                       or                           ⇒ x= - 1/3
α=3/2 ,β= - 1/3
⇒α+β= -b/a
⇒3/2+(-1/3)= - (-3)/6
⇒3/2-1/3=1/2
⇒7/6 =1/2
 ⇒αβ=c/a
 ⇒ 3/2(-1/3)= -7/6
⇒-1/2= -7/6
 ⇒1/2=7/6      

Answer: (a) Nationalism is a feeling that combines all the people of the nation into a single unit. It is a powerful sentiment that binds people together in a common bond beyond their communal, lingual, caste or religious differences. In all the colonies of the world, the imperialist power exploited the people socially, religiously, economically and politically.

• Colonization affected people’s freedom, and nationalist sentiments surged during the process of struggle against imperial domination.
• The sense of oppression and exploitation became a common bond for people from different walks of life, and this resulted in the growth of nationalist ideals.
• Although each class or group of people felt that they were being oppressed under colonialism, the effects of colonialism were felt differently.
• People started uniting against the colonialism which strengthened the sense of nationalism further.

Thus, the growth of nationalism in the colonies is linked to anti-colonial movements.

For more click on the given link:

<a href="https://mycbseguide.com/blog/ncert-solutions-for-class-10-social-science-history-nationalism-in-india/">https://mycbseguide.com/blog/ncert-solutions-for-class-10-social-science-history-nationalism-in-india/</a>

• Reaction of Acids with Metals:

When an acid reacts with a metal, then a salt and hydrogen gas is formed.

Acid + Metal → Salt + Hydrogen gas

Example - When  dilute  hydrochloric  acid  reacts  with the  metal zinc,  zinc  chloride is  formed  with  the  evolution  of hydrogen gas.

When the reaction between an acid and a metal takes place, there will be formation of gas bubbles.

When these gas bubbles are passed through soap solution, gas filled soap bubbles rise into the air. When a burning candle is brought near a gas-filled soap bubble, the gas present in the soap-bubble burns with a 'pop' sound. Only hydrogen gas burns making a 'pop' sound. This shows that hydrogen gas is evolved in the process.

• How do Metal Carbonates and Metal Hydrogencarbonates React with Acids?

When an acid reacts with a metal carbonate then a salt, carbon dioxide and water are produced.

Example: When dilute hydrochloric acid reacts with sodium carbonate, then sodium chloride, carbon dioxide and water are formed.

When an acid reacts with a metal hydrogen carbonate, then a salt, carbon dioxide gas and water are formed.

All metal carbonates and hydrogencarbonates react with acids to give a corresponding salt, carbon dioxide and water.

Hence, the reaction when metal carbonates and hydrogencarbonates react with acids can be summed up as:

Metal carbonate/Metal hydrogencarbonate + Acid → Salt + Carbon dioxide + Water

• How do Acids and Bases React with each other?

The reaction between an acid and a base to form salt and water is called a neutralisation reaction.

Base + Acid → Salt + Water

When hydrochloric acid reacts with sodium hydroxide solution, then a neutralisation reaction takes place to form sodium chloride and water.

• Reaction of Metallic Oxides with Acids:

Acids react with metal to form salt and water.

Metal oxide + Acid → Salt + Water

Example: Copper Oxide is a metal oxide. Dilute hydrochloric acid reacts with copper oxide to form copper chloride and water;

• Reaction of a Non-metallic Oxide with Base:

Bases react with non-metallic oxides to form salt and water.

For Example: Calcium hydroxide reacts with non-metallic oxides like carbon dioxide to form calcium carbonate salt and water.

Ca(OH)₂ + CO₂ → CaCO₃ + H₂O

• What Do All Acids And All Bases have in Common?

Acids:

An acid is a substance which dissociates (or ionises) when dissolved in water to release hydrogen ions.

For Example:

An aqueous solution of hydrochloric acid dissociates to form hydrogen ions. Since hydrogen ions do not exist as H+ in solution, they combine with polar water molecules to form hydronium ions [H3O⁺].

HCl_(aq) → H⁺_(aq) + Cl^-_(aq)

H⁺+ H₂O → H₃O⁺ 

The presence of hydrogen ions [H⁺] in hydrochloric acid solution makes it behave like an acid.

TRANSPORTATION IN PLANTS

Soil is the natural and richest source of raw material for plants.

Raw materials like nitrogen, phosphorous and other minerals are absorbed by plants from soil by roots.

Plants absorb water and minerals from soil by roots and transport to the leaves.

As the distance between roots and leaves is large, diffusion is not sufficient to provide raw materials to leaves and energy to roots.

Plants use slow transport system but large as required in tall plants to transport energy from leaves and raw materials form roots.

A group of special cells forming vascular tissue transport water and nutrients to all the cells of the plants.

Two types of vascular tissues are xylem and phloem.

Xylem transports water and minerals obtained from the soil.

Phloem transports products of photosynthesis from the leaves to other parts of the plant.

Vessels, tracheids of the roots, stems and leaves are connected to form a continuous system in xylem cells to transport water to all the parts of the plants.

Cells in the roots which are in contact with the soil take up ions which creates a difference of concentration between the roots and the soil and therefore water moves to the roots to eliminate the difference.

Water is moved into xylem of roots and from where it is pushed upward.

Plants use different mechanisms to pull water upwards through xylem like-

• Water which is lost through stomata is replaced by water absorbed by the roots.
• Evaporation of water from leaf creates a suction force which pulls water.

The loss of water in the form of water vapor is called

Importance of transpiration-

• Regulates temperature.
• Helps in absorption of water and upward movement of water and minerals.

When stomata are open during the day, large amount of water is lost and thus upward movement of water also becomes more.

Phloem transports soluble products of photosynthesis, amino acids, and other substances.

The transport of soluble products of photosynthesis is called translocation.

The substances are transported to the storage organs of roots, fruits and seeds.

The translocation takes place in the sieve tubes with the help of adjacent companion cells.

The movement of substances is bidirectional i.e both upward and downward.

Energy from ATP is utilized for translocation.

Materials like sucrose move to phloem using energy, increasing the osmotic pressure of the tissue causing water to move and materials in the phloem to tissues according to the plant’s needs.

Example- when the buds grow t

The blood clots if conducting tubes of a circulatory system develops a leak. The platelets will increase, which will minimize the leakage. Due to this, the inactive thrombin will become the active one in the presence of thromboplasm. Moreover, this active thrombin will convert the inactive fibrinogen into the active fibrin and it results with a clot. The problem is that if the person doesn’t develop with a blood clot, then the medical care is required, otherwise this can lead to death.

1. Gaseous exchange takes place within the lungs by diffusion from the alveoli to blood capillaries and vice versa. Alveoli in lungs are numerous and only one cell thick.
2. Alveoli are surrounded by capillaries that are also one cell thick.
3. Blood, dark red in colour flows from the heart through these capillaries and collects oxygen from the alveoli.
4. At the same time, carbon diox¬ide passes out of the capillaries and into the alveoli.
5. When we breathe out, we get rid of carbon dioxide.
6. The bright red, oxygen rich blood is returned to the heart and pumped out to all parts of the body.

Structure of Human Heart

• The heart is a muscular organ covered by a double membrane called pericardium.
• The pericardial fluid of the pericardium lubricates the heart.
• The heart is divided into four chambers — two upper atria and two lower ventricles.
• The inter-atrial septum separates the two atria and the inter-ventricular septum separates the two ventricles.
• The atrium and the ventricle of each side are separated by the atrioventricular septum.
• Superior and inferior vena cavae open into the right atrium.
• The right ventricle opens into the pulmonary artery.
• Four pulmonary veins open into the left atrium.
• The left ventricle opens into the aorta.
• The opening between the right atrium and right ventricle is guarded by the tricuspid valve.
• The opening between the left atrium and left ventricle is guarded by the bicuspid (mitral) valve.
• The opening of the right ventricle into the pulmonary artery and the opening of the left ventricle into the aorta is guarded by the semilunar valves.

Working of Heart

The right atrium receives blood from the upper and lower body through the superior vena cava and the inferior vena cava, respectively, and from the heart muscle itself through the coronary sinus. The right atrium is the larger of the two atria, having very thin walls. The right atrium opens into the right ventricle through the right atrioventricular valve(tricuspid), which only allows the blood to flow from the atria into the ventricle, but not in the reverse direction.

The right ventricle pumps the blood to the lungs to be reoxygenated.

The left atrium receives blood from the lungs via the four pulmonary veins. It is smaller than the right atrium but has thicker walls. The valve between the left atrium and the left ventricle, the left atrioventricular valve(bicuspid), is smaller than the tricuspid. It opens into the left ventricle and again is a one-way valve.

The left ventricle pumps the blood throughout the body through the aorta, which is the largest artery in the body. The walls of the left ventricle are the thickest among all the chambers.

The growth of population increased the demand of food grains in Britain. The landed aristocracy pressurised the government to restrict the import of corn into the country. These laws came to be known as the Corn Laws. The promulgation of the Corn Laws further pushed up the prices of food grains. The industrialists and urban dwellers were unhappy with the Corn Laws which resulted in the government abolishing the laws. After the abolition of the Corn Laws, imported food flooded the British markets. British agriculture was not able to compete with imports. This resulted in the abandonment of cultivation in many agricultural fields of Britain. Many farmers migrated to urban centers in search of employment opportunities.

Sum of roots = -( coeff.of x)/coeff.of x^2
2+3 = -(-2k)/3
5 = 2k/3
2k = 15
k = 15/2

Product of roots = constant term/ coeff.of x^2

2×3 = 2m/3
6 = 2m/3
m = 6 × 3/2 = 9