A river which does not change its alignment – slope and its regime significantly is called________?

Specific heat is higher in:

The minimum moisture content at which a water drop if placed on a smooth surface of soil will not be absorbed immediately by the soil is called ________?

The investment of private foreign funds in the economy of a developing nation?

Tea is the example of fermentation of________?

Obtaining the socially optimal amounts of goods and services using minimum necessary resources?