The main features of Mauryan administration were:

• There were five important political centres in the Mauryan Empire: Patliputra (the capital city) and the provincial centres of Taxila, Ujjayini, Tosali and Suvarnagiri.
• It was not possible for such a large empire to have a uniform administrative system so historians believe that the administrative control was perhaps strongest in the capital and in provincial centres.
• Communications along the land and riverine routes were developed to administer the Empire.
• The army was an important tool for not only extending the territories of the empire but also for administering them.
• Committees and sub-committees were formed for coordinating military activities. They looked after the navy, horses, chariots, elephants, recruiting soldiers and managing transport and food supplies for soldiers.
• Asoka held his Empire together by propagating the doctrine of Dhamma, whose principles were simple and universally applicable. The doctrine propagated the ideas of peace, non-violence and respect towards elders. Dhamma mahamatt as were appointed to spread the principles of Dhamma.
• The last feature of the Mauryan administration is evident in the Asokan inscriptions that we have studied. It is because Ashoka inscribed the main features of his policy of ‘dhamma’. According to the inscriptions, he had also appointed Special officers called Dhamma Mahamtras to spread Dhamma.

The study of inscription is known as Epigraphy inscriptions were engraved or carved on seal , stone , pillars , copper plates , ivory , Temple wall , and images . The kings of ancient India tried to glorify themselves through inscription. James Princep first deciphered indian inscription in 1837 the inscription are of various type like euology and prasasti, commemorative, religious, royal orders , records of donations , gifts etc.

The following are the main principles of Ashoka’s dhamma:

1. People should live in peace and harmony.
2. Everyone should practise the principle of ahimsa, i.e. non-violence and non-injury to all living beings.
3. People should love one another and display respect and tolerance towards other religious faiths.
4. Children should obey their elders and elders should treat children with understanding.
5. People should be truthful, charitable and kind to all, even towards servants and slaves.

Features of teh Mahajanpads were:

• Mahajanpads were forms of early states which were formed after combining several 'janas'. In sixth century BCE ancient India, there were 16 mahajanpads. 
• While some mahajanpads had a monarchial form of governement ruled by the king, others were 'gana' or 'sanghas' or oligarchies. They were ruled by a group of people.
• Each mahajanpad had its own fortified capital city. The king lived in the capital.
• As mahajanpads developed, they built large standing armies and the system of bureaucracy to administer states.
• The king collected taxes from the people and spent the revenues on state administration and building of armies.

The Magadha Empire was the most powerful Kingdom in Ancient India. It had powerful kings like Bimbisara, Ajatasatru, Dhana Nanda, Chandragupta Maurya, etc.
This rise of Magadha Imperialism is unique in Indian history. The political history of India from the earliest times till the present day is an endless story of struggle between the forces of centralization and decentralization.
In the sixth century B.C., India presented the chronic symptom of disintegration. The Aryan India in the North was divided into, sixteen great kingdoms and a number of republican, autonomous states.
Out of the medley of political atoms, four kingdoms viz., Avanti, Vatsa, Kosala and Magadha, Magadha Empire rose into prominence by aggrandizing upon other weaker states. They entered into a four-power conflict for imperial supremacy which ended in the ultimate victory of Magadha Kingdom over them. It is the first successful attempt for imperial and dynastic unification of India in the period of recorded history.
One of the main factors behind the rise of Magadhan Power was her economic solvency and growing prosperity. Magadha had a vast population which could be employed in agriculture, mining and for manning her army. The Sudras and the non-Aryans could be employed in clearing up the forest and reclaim surplus land for farming. The surplus population could easily live on the yield of the surplus land. The Magadhan lands were very fertile due to its location between the Ganges and the Son. In the 4th Century B.C. that the Magadhan lands yielded multiple crops round the year. People of Magadhan Empire became prosperous due to fertility of the land and the government became automatically rich and powerful.

MicroEconomics is no more in class 12th syllabus.

By the way, PPC (production possibility Curve) is a curve that shows the combination of two goods which can be produced at the given level of resources and technology.

Production Possibility Curve (PPC) is concave to the origin because of the increasing opportunity cost. As we move down along the PPC, to produce each additional unit of one good, more and more units of other good need to be sacrificed. That is, as we move down along the PPC, the opportunity cost increases. And this causes the concave shape of PPC.

A gold-leaf electroscope is a simple device which is used to identify the electric charge present in a body.Their operation is based on the principle of like sign charge repulsion. Two sheets or leaves, cut longer than they are wide and made of very thin, electrically conductive material, are hung adjacent and virtually in contact with each other. The leaves are ordinarily made of material sufficiently thin so that they have no rigidity and hang down limply. When the leaves, which are electrically connected, become electrically charged, they push apart from each other. The angle they form correlates on the amount of electric charge on the leaves. See the figure below. If the instrument is shielded so that the capacitance is fixed, then the angle can be with some precision to static voltage. It should be noted that the electroscope actually indicates potential, not charge.

The leaf electroscope does not distinguish positive from negative charge, though there are some simple methods for doing so.

In a calibrated electroscope, the two leaves are made of fine hammered gold leaf and the voltage is determined by viewing and measuring the separation angle with a low-power microscope

Natural Birth Control

Natural birth control methods include total and continuous abstinence and the rhythm method. The rhythm method involves having no intercourse or protected intercourse during the time when the woman is fertile. A woman is fertile for 9 days every month during which she is most likely to conceive. The fertile period starts 5 days before ovulation and continues for 3 days after ovulation.

Money flow refers to the flow of money in terms of receipts and payments across different sectors of the economy. Flow of factor payments by producer sector to the household sector or flow of money from household sector to producer sector on account of the purchase of goods and services for consumption are examples of money flows.
Real flow refers to the flow of goods and services across different sectors of the economy. Flow of factor services from household sector to the producer sector or flow of goods and services from producer sector to household sector are examples of real flows.

Band theory of solids

In a substance, as many atoms are close to each other, the energy levels of the atom form a continuous band, where in the electrons move.  This is called band theory of solids.

Cell division is the driving process of reproduction at the cellular level. Most eukaryotic cells divide in a manner where the ploidy or the number of chromosomes remains the same, except in the case of germ cells where the number of chromosomes is halved.

Pollen or nectar robbers are those animals, insects, birds that removes the nectar from a flowering plant without causing pollination.

Endosperm

• Primary Endosperm Cell (PEC) formed as a result of triple fusion undergoes repeated divisions and a triploid endosperm tissue is formed. The main purpose of endosperm is to provide nutrition to the developing embryo.
• Endosperm can be free-nuclear or cellular. Free-nuclear endosperm is the most common type of endosperm development. The best example to understand is the tender coconut.
• In a tender coconut, water present inside is the free-nuclear endosperm. Multiple nuclei float in this highly nutritious clear fluid. Gradually cell walls develop enclosing several nuclei. These cells & nuclei start settling at the periphery, and layers of cellular endosperm start appearing. Therefore, in a completely mature coconut, water turns milky surrounded by cellular part, kernel & it does not contain free nuclei.

The Harappan and the Mohenjodaro cities were known as well-planned cities because:

• The settlement was divided into two sections: Citadel (built on a higher elevation) and Lower Town. The Citadel was walled and separated from the Lower Town. The Lower Town was also walled.
• Bricks used in building the city’s houses were of standardised ratio.
• Roads in the cities were laid out along a grid pattern intersecting each other at right angles.
• The cities of the Indus Valley Civilisation had an advanced system of drainage. Every house was connected to the street drain. House drains emptied themselves into the main drain.  
• The drainage system and drains were covered with bricks or stones. They were provided with inspection holes at regular intervals for cleaning.
• House drains first emptied into sumps into which solid matter settled and wastewater flowed into the street drains.

The 1991 Indian economic crisis was an economic crisis in India that resulted from poor economic policies and the resulting trade deficits. ... By the end of 1990, in the run-up to the Gulf War, the dire situation meant that the Indian foreign exchange reserves could have barely financed three weeks' worth of imports. The New Industrial Policy established in 1991 sought substantially to deregulate industry so as to promote growth of a more efficient and competitive industrial economy. The central elements of industrial policy reforms were as follows: Industrial licensing was abolished for all projects except in 18 industries.