Questions

Variable costs are expenses that vary in proportion to the amount of goods or services that a business produces. 

Examples of variable cost include labor, packaging and raw materials.

Crop Rotation is the practice of growing a series of dissimilar or different types of crops in the same area in sequenced seasons. It is done so that the soil of farms is not used for only one set of nutrients. It helps in reducing soil erosion and increases soil fertility and crop yield. The British agriculturist Charles Townshend (1674–1738) popularised this revolutionary technique in the 18th century.

All the above given options are the examples of social interaction. In sociology, interactions are of five types.They are :

1) Exchange

2) Competition

3) Cooperation

4) Coercion

5) Conflict

In an ideal gas, at any particular time, different particles in the gas have different speeds and hence different kinetic energies. This assumption is reasonable because as the particles collide, we expect their speed to change. Even if initial speed of all the particles was same, the molecular collisions will disrupt this uniformity.Hence statement 1 is incorrect and 2 is correct.