Relationship among Total, Average and Marginal Products.

Stages	Total Product	Marginal Product	Average Product
Stage - I	It increases at an increasing rate. Then it increases at a decreasing rate. This is the point of inflexion.	It increases, reaches maximum and starts to decrease.	It increases, reaches maximum.
Stage - II	It continues to increase at a diminishing rate and reaches maximum	It continues to diminish and becomes zero.	It is equal to MP then begins to diminish.
Stage - III	It diminishes.	It becomes negative.	It diminishes but always greater than zero (positive)

(i) Elasticity of supply is the degree of responsiveness of change in supply to change in price on the part of sellers.
(ii) There are 5 types of elasticity of supply:
1. Relatively elastic supply
2. Relatively inelastic supply
3. Unitary elastic supply
4. Perfectly elastic supply
5. Perfectly inelastic supply
(iii) The factors governing elasticity of supply are the nature of the commodity, cost of production, technical condition & time factor.

Initiation: He considers the situation and availability of resources and plans the process of production.
Innovation: He introduces new methods in the production process.
Co-ordination: He uses a particular combination of the factors of production.
Control, direction & supervision: He directs the factors to get better results and supervises for the efficient functioning of all factors.
Risk taking, uncertainty bearing: Risk is insured, uncertainties cannot be insured.

Nature of the commodity:
(i) Durable goods can be stored for long till price increases so elasticity of supply is high.
(ii) Perishables have to be sold immediately, so elasticity of supply is low.
Cost of production:
When there is constant or increasing returns, supply increases so elasticity of supply is greater.
Technology:
In large-scale production with huge capital investment supply cannot be adjusted easily, so elasticity of supply is less.
Time factor:
During very short period, supply cannot be adjusted, so elasticity of supply is very low.

Land is a primary factor of production.
1. It is a passive factor.
2. It is a free gift of nature.
3. It has no cost of production.
4. Its supply is inelastic.
5. It is permanent. 
6. It is immovable.
7. It is heterogeneous.
8. The fertility differs.
9. It has alternative uses.
10. It faces law of diminishing returns.