Mesopotamian society the nuclear family was the norm, although a married son and his family often resided with his parents. The father was the head of the family.

• A ruling elite had emerged
• Had a major share of wealth
• Followed nuclear family system and  patriarchal system
• Condition of women
• System of marriages

Town Planning: The discovery of the Sumerian city of Ur has shed light on the lives of the early Mesopotamians. The Mesopotamian cities fell short in terms of town planning as compared to the Harappan centres but followed a uniform pattern nevertheless. The city was divided into three parts - the sacred area, the walled city on a mound and the outer town. The sacred area consisted of the temple tower or the <i>ziggurat </i>dedicated to the patron god of the city. There were also smaller temples of other gods. This area also had the storehouse as well as the offices. People resided in the walled city and the outer town areas. Houses were constructed along the streets, and each house had a central courtyard with rooms attached around it.

The legacy of Mesopotamia to the world
a. The legacy of Mesopotamia is very rich and massive spreading throughout the world.
b. The future civilizations imbibed the legacy of Mesopotamia and the legacy set a precedent for the civilization.

c. The land of Mesopotamia left the legacies of urbanization, 

The single-celled prokaryotic microorganisms with various range of characteristics are called Eubacteria or true bacteria. These types of microorganisms are found in almost all conditions. They do not consist of membrane nuclei. The cell wall of Eubacteria is made up of peptidoglycans in a cross-linked chain pattern.

• Seafloor spreading is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.

• Seafloor spreading helps explain continental drift in the theory of plate tectonics.

• This theory was proposed by Hess in 1961. He argued that constant eruptions at the crest of oceanic ridges cause the rupture of the oceanic crust and the new lava wedges into it, pushing the oceanic crust on either side. Thus,the ocean floor spreads.

• The younger age of the oceanic crust as well as the fact that the spreading of one ocean does not cause the shrinking of the other, made Hess think about the consumption of the oceanic crust.

• He further maintained that the ocean floor that gets pushed due to volcanic eruptions at the crest, sinks down at the oceanic trenches and gets consumed.

Internal Trade :
Internal trade is done within the geographical boundaries of a country. As an example, trade done amongst the traders of Delhi, Mumbai, Chennai, Kanpur and Amritsar etc. is called Internal Trade.

Types of Internal Trade :

(i) Wholesale Trade : It involves purchase and sale of goods in wholesale quantities. Large quantities of goods purchased from manufacturer are sold in small quantities to various retailers.

(ii) Retail : It involves the sale of goods to consumers by the retailers. A retailer buys the goods from a wholesaler and sells them to customers in their required quantities. It is a link between a wholesaler and consumer. Different types of goods are available at a retailer shop so that a customer could buy the goods of his own choice.

Internal trade can also be classified as : (a) Local Trade, (b) State Trade, (c) Inter-State Trade.

External Trade : 
Whenever trade occurs between two countries, it is known as external trade. In foreign trade, both buyer and seller live in different countries. If Reliance Ltd. sells Polyester Yarn to a French firm or L&T Ltd. purchases a heavy machine from a Swiss firm, these would classified as external trade.

Types of External Trade :

1. Import Trade : When the trader of one country buys the goods from foreign countries, it is known as import trade for the trader who buys the goods.

2. Export Trade : When the trader of a country sells goods to a foreign country, it is known as export trade for the trade who sells the goods e.g., if a tea firm of Darjeeling sells tea to U.K., it is export trade.

3. Entrepot Trade : The goods imported from one country for export to another country, is known as entrepot trade. It is also known as Re-export. It is done when a country does not have her own seaport or not having good political relations with other countries or no direct access to those countries from where goods are to be imported.

A mass of data in its original form is called raw data. It is an unorganized mass of various items. A characteristic which is capable of being measured and changes its value overtime is called a variable.

If a good can be used for many purposes, the demand for it will be more elastic because with a decrease in its price, it can be put to several uses and with a rise in its price, it is withdrawn from its many existing uses.
So that, there is a considerable change in demand in response to some changes in price, e.g. milk.

Journal proper is book of original entry (simple journal) in which miscellaneous credit transactions which do not fit in any other books are recorded. It is also called miscellaneous journal. The form and procedure for maintaining this journal is the same that of simple journal. Books with original entries used for miscellaneous credit transactions that do not fit into other recorded books. The journal is maintained like a simple journal to record opening entries, closing entries, transfer entries, adjustment entries, rectification entries, and rare transactions.

In molecular geometry, bond length or bond distance is defined as the average distance between nuclei of two bonded atoms in a molecule. It is a transferable property of a bond between atoms of fixed types, relatively independent of the rest of the molecule. Bond parameters refer to the characterization of covalent bond on the basis of various parameters like bond length, bond angle, bond enthalpy. Bond length is defined as the equilibrium distance between the nuclei of two bonded atoms in a molecule. Bond lengths are measured by spectroscopic X-ray diffraction and electron-diffraction techniques. In the case of a covalent bond, the contribution from each atom is called the covalent radius of that atom.

The allocation of resources is considered as inefficient if the combination of the goods produced lies inside the PPC curve. An Any point lying under the curve , like F, depicts inefficiency or underutilisation of available resources .

It is true ‘The Address’ is a short story highlighting human predicament that follows war. The story beautifully delineates the pain, anguish, and mental torture of the survivors of war. The narrator, Margo Minco, a Jew, returned back to her native city after the War was over. She had already suffered many losses, including the irreparable loss of her dear mother. After the war, she faced the loneliness and challenges alone. She went to Mrs. Dorling to get her mother’s cutlery, crockery, utensils, and other household things; Mrs. Dorling’s cold, indifferent and discouraging behavior further depressed her. Finally she decided to leave her mother’s things and forget them forever.