26) Consumptive use of water by a crop is equal to

• (a) the depth of water consumed by evaporation
• (b) the depth of water consumed by transpiration
• (c) the depth of water consumed by evaporation and transpiration during crop growth, including water consumed by accompanying weed growth
• (d) none of the above

27) The consumptive use of water of a crop

• (a) is measured as the volume of water per unit area
• (b) is measured as depth of water on irrigated area
• (c) may be supplied partly by precipitation and partly by irrigation
• (d) all of the above

28) Which of the following statement is correct ?

• (a) The gravity water is harmful to the crops.
• (b) The hygroscopic water remains attached to the soil molecules by chemical bonds.
• (c) The capillary water is utilised by the plants.
• (d) all of the above

29) The ratio between the area of a crop irrigated and the quantity of water required during its entire period of the growth, is known as

• (a) delta
• (b) duty
• (c) base period
• (d) crop period

30) The total depth of water required by a crop during the entire period the crop is in the field, is known as

• (a) delta
• (b) duty
• (c) base period
• (d) crop period