It will be decided by your subject teacher.

“Pollution” is the mixing/blending of foreign or unwanted agents into some element or compound, which thereby, reduces its quality, by causing “Degradation”. “Pollution” and “Degradation” are directly proportional to each other. The more the pollution, the more the degradation.

For example, mixing waste products with water and smoke with air causes water pollution and air pollution, respectively. This pollution lowers the quality of water for consumption and air for respiration, thus causing water pollution and air pollution, respectively. Thus, more pollution means more degradation.

Physical geography is that branch of natural science which deals with the study of processes and patterns in the natural environment like the atmosphere, hydrosphere, biosphere, and geosphere, as opposed to the cultural or built environment, the domain of human geography.

Areas of physical geography include:

• Geomorphology: the shape of the Earth’s surface and how it came about
• Hydrology: the Earth’s water
• Glaciology: glaciers and ice sheets
• Biogeography: species, how they are distributed and why
• Climatology: the climate
• Pedology: soils
• Palaeogeography: how the continents have moved over time
• Coastal geography: how the ocean and land affect each other
• Oceanography: the oceans and seas
• Quaternary science: the geography of the last 2.6 million years, including the last ice age
• Landscape ecology: how the landscape affects things like the distribution of plants and animals
• Geomatics: gathering, storing and processing geographic information – for example, making maps

Instructive (comparative more instructive, superlative most instructive) Conveying knowledge, information or instruction.
Well, that was an instructive lesson.

The branches are:
(i) Physical Geography: It includes Geomorphology, Climatology, Hydrology and Soil Geography.
(ii) Human Geography: It includes Cultural Geography, Population and Settlement Geography, Economic Geography, Historical Geography and Political Geography.
(iii) Bio-Geography : It includes Plant Geography, Zoogeography, Ecology and Environmental Geography.

Many Sciences developed to describe the physical features of the earth such as Geology, Pedology, Oceanography Botany Zoology and Meteorology & Cultural features of the earth such as Economics, History, Sociology Political Science, Anthropology,

Volcanoes are grouped into four types:

• Cinder cones
• Composite volcanoes
• Shield volcanoes
• Lava volcanoes

Cinder cones are circular or oval cones made up of small fragments of lava from a single vent that have been blown up. Cinder cones result from eruptions of mostly small pieces of scoria and pyroclastics that build up around the vent.
Composite volcanoes are steep-sided volcanoes composed of many layers of volcanic rocks, usually made from high-viscosity lava, ash and rock debris. These types of volcanoes are tall conical mountains composed of lava flows and other ejecta in alternate layers, the strata that gives rise to the name.
Shield volcanoes are volcanoes shaped like a bowl or shield in the middle with long gentle slopes made by basaltic lava flows. These are formed by the eruption of low-viscosity lava that can flow a great distance from a vent.
Lava domes are formed when erupting lava is too thick to flow and makes a steep-sided mound as the lava piles up near the volcanic vent. They are built by slow eruptions of highly viscous lava.

1. It is influenced by the mountains and relief features of the country. For example, the western slopes of the Western Ghats get heavy rainfall while the eastern slopes get scanty rainfall as the latter lies on the leeward side of the Western Ghats.
2. Monsoon rainfall in India is unevenly distributed in the country. While Meghalaya receive more than 200 cm of rainfall, the western parts of Rajasthan and Punjab get only up to 50-80 cm of rainfall annually.

The regular rise and fall of the ocean’s waters are known as tides. It is high tide when water covers much of the shore by rising to its highest level. It is low tide when water falls to its lowest level and recedes from the shore.

Some of the importance of tides is discussed below:

1. Fishing: Tides affect other aspects of oceanic life, including the reproductive activities of fish and ocean plants. 

2. Tidal Zone Foods: Edible sea creatures like Crabs, mussels, snails, seaweed etc. inhabit the tidal zone and the most important point to be remembering that without the regular washing of the tides, these complex and abundant creatures would die and food resources would diminish.

3. Navigation: High tides help in navigation. They raise the water level close to the shores which helps the ships to arrive at the harbour more easily.

4. Weather: Tides stirred the ocean water that makes habitable climatic condition and balance the temperatures on the planets.

5. Tidal Energy: In every 24 hour, two high tides and two low tides occur. Hence, the fast movement of water during the inflow and outflow will provide a source of renewable energy to communities living along the coast.

Characteristics of tropical evergreen forests are
(i) The trees reach a great height upto 60 m or even above. Trees are tall, thick and have vigorous growth.
(ii) As the region is warm and wet throughout the year, it has a luxuriant vegetation of all kinds-trees, shrubs and creepers giving it a multilayered structure.
(iii) There is no definite time for trees to shed their leaves, as such these forests appear green all the year round.

Kangchenjunga section contains five peaks and the region has 12 more peaks over 7,000 m (23,000 ft). The highest mountain Kangchenjunga is located at the border of India and Nepal in the great Himalayas range, Sikkim.