1. What you mean by demand ? 

Demand is desire backed by ability and willingness to pay for a commodity the demand always at price without price the term demand has to meaning. The demand for a particular commodity changes according to its price. At a lower price more quantity will be demanded and only less at higher price. Here demand and price have to relationship.

2. Definition of Demand .
According to Hansen says “by demand – we mean the quantity of a commodity that will be purchased at a particular price and not mean up the desire of a thing.

3. What are the features of demand ?
The main features of demand are:
1. Desire and Demand :There is a different between desire and demand as former is only a wish while demand empties that consumer has the willingness and ability to keep certain commodity in the market at a given prices.
2. Demand and price :Demand always at a price per unit of time without price the demand for a commodity has no meaning. In fact every consumer must know at what price he is ready to demand a commodity.
3. Demand a point of time: Another features of demand is that is always reinforced at a given period of time.

4. What are the type of demand ?
Their are eight type of demand. They are:
1. Price demand
2. Income demand
3. Cross demand
4. Direct and indirect demand
5. Joint and composite demand
6. Alternative demand
7. Derived demand
8. Competitive demand

5. What are the factor influencing demand ?
1. Price of a commodity
2. Price or related goods
3. Income of the consumer
4. Distribution of wealth
5. Tastes and preferences
6. Government policy
7. State of business
8. Population growth
9. Climate and wealth
10. Savings

6. Why does the demand curve slope downwards ?
 It is the general law that the demand curve slope downward to the right. It shows an inverse relationship between price and demand. There are several reasons responsible for the inverse price and demand relationship as explained under:

1. The law of diminishing marginal utility: The law of demand based on the utility diminishing marginal utility. According to law When a consumer consume more and more unit of commodity satisfaction form the secondary units become less and less. The law explains that an individual will purchase more units of a commodity only when the price falls.

2. Income effect : Income effect means the effect of change in income when the price of a commodity falls. That is when a price of a commodity falls real income of the consumer increases. In this the consumer can purchase the same quantity of a commodity with a less amount. The amount is saved can be used for purchasing some more units of a commodity this bring about increase in demand when price falls.

3. Substitution effect : A full in price of a commodity makes it comparatively cheaper to the three commodities. As the price of a commodity falls, prices of its substitute goods remain the same, the consumer will buy more of that commodity. Therefore, with a fall in price, the demand will increase due to favourable substitution effect.

4. Increase and decrease in demand : Increase and decrease in demand area change in demand due to the change in non price factors. An increase in demand means either more quantity at a same price or the some quantity at a higher price. A decrease in demand means either less quantity at a same price or the same quantity at the lower price.

7. Difference between extension of demand and increase in demand.
Extension demand  :It is a situation when the demand of the commodity increases with the fall in price other things equal fall in price. The extension demand curve moves downward.
Increase demand: It is a situation when the demand of the commodity use due to factors other than price the demand increase due to ‘increase in consumer’ income, increase in the price of substitute and change in the consumer’s taste and preference etc. The movement of the curve shifts towards right.

8. Difference between contraction of demand and decrease in demand.
Contraction of demand: It is a situation when the demand of a commodity decreases with the rise in price other things being equal. The demand curve moves form downward to the upward.

Decrease demand: It is a situation when the demand of a commodity falls due to factors other than price. The demand decrease due to decrease in consumers income falls in the price of substitution and falls in the price of substitutes and falls in the taste of the consumer towards that commodity. The movement of the curve shift towards the left or downward.

9. Difference between increase in demand and decreasing demand.
Increase in demand means more demand at same price or same demand at more price is called increase in demand.
Decrease in demand means less demand at the same price and same demand at less price is called decrease in demand.

10. Define market demand schedule and market demand curve.
Market demand schedule is defined as the quantities of a given commodity which all consumers will buy at all possible prices at given moment of time. A market demand curve represents combinations of demand of different consumer at different prices.

11. What are the factors influence demand of a commodity ?
The factor which influence demand of a commodity are
1. Price of a commodity
2. Income of the consumer
3. Distribution of wealth
4. Population
5. Taste and preferences and government policy.

12.Define supply.
The term supply of a commodity means the various amounts of the commodity which are supplied at different prices in the market. Just as demand for a product is always at a price supply of a commodity is also at a price. Supply raises with price and it has meaning only with reference to some time period.  According to Anatol Murad Sarps that “ supply refers to the quantity of a commodity offered for sale at given price in a given market at a given time”.

13. What are the factors influencing supply?
The following are the some of the factor influencing supply of a commodity.
1. Goals of the firm: The most important goal of a firm is to maximize profit. Profit is the difference between revenue and cost. Profit is maximum when total revenue is the  maximum and total cost, the maximum. The other goals of the firm are minimum sales, maximum share of the market, maximum production etc.

2. The price of the commodity: The amount of a commodity supplied by a firm depends upon the price of the commodity.

3. The price of other commodities : The supply of commodity depends upon the prices of all other commodities. If the prices of other commodities rise the production and supply of those commodities will become cheap, the price of which has not fallen , will become less attractive and so its supply will fall.
4. The state of Technology : The technological advancement advancement map reduce the cost of production of commodities scientific discoveries and other application to commercial
production of a commodities have brought about changes in the supply of commodities.

14. What is law of supply ?
Other things remaining the same supply of a commodity expands with rise in price and contract with a fall in price the law of supply. Shows the relationship between price and quantity supplied. Generally the supply of a commodity varies directly with its price. The higher the price the larger the supply and lower the price the smaller the supply.
Assumption of the law of supply.
1. The goals of the firm
2. The price of a commodity
3. The price of the other commodities
4. There is no expectation of change in the price of the commodity
5. There is no change in the technique of production

15. What is supply schedule and supply curve ?
Supply schedule is the table which shows the amount of a commodity supplied directing a given period of different prices.Supply curve is a graphical representation of a supply schedule showing the relation between price and quantity supplied. Supply curve slopes upwards from left to right relating that more will be supplied at higher price and quantity less lower price.

16. What are the exceptions of law of supply?
1. The law does not apply in case of agricultural products, whose supply is affected by national factors.
2. The law may not apply in case of these goods sellers may be wiling to sell more into at declining price.
3. The law may not apply in case of goods having social distinction . The supply of these good will remain limited even of there prices are high.

17. What are the reasons for increasing supply?
I. Fall in the prices of related goods
II. Changes in the goals of producers
III. Fall in the price of factors of production
IV. Improvements of technology
V. Increase in the number of firms in the market
VI. Subsides offered by the government.
VII. When the firm experts a fall in the price of the commodity.

18. What are the reason for decreasing supply ?
I. Rise in the price of the related commodities
II. Changes in the goals of the producer.
III. Rice in the price of factor of production
IV. Fall in the level of technology.
V. Decrease in the number of firm in the market
VI. When the firm expects a rise in the price of the commodity.

19. What are the importance of elasticity of supply ?  
1. Effect price : - The elasticity of supply is useful to assess the effect or rice when the demand of a commodity increases. The more elastic in supply, the
smaller the rise in price. This tempts the sellers to offer more commodity for sale.
2. Quasi – Rent.
In order to understand the quasi rent which one enjoys, elasticity of supply helps to make a difference between short run elasticity and long run elasticity of
supply.
3. Better for economic planning.
The knowledge of elasticity of supply is useful to understand the concept of economic planning specially in less developed countries.