Question

question 4 (1 point)
the presence of harmful substances like chemicals or bacteria in water is called:
o a evaporation
o b irrigation
o c contamination
o d conservation

question 5 (1 point)
why should farmers care about the ph of irrigation water?
o a it changes the crop color
o b it can lock up soil nutrients if too acidic or too alkaline
o c it increases soil erosion
o d it always helps plants grow bigger

question 6 (1 point)
what is the main role of conservation in irrigation?
o a increasing water use
o b adding salt to water
o c careful management to prevent waste
o d wasting more water

Explanation:

Question 4

Evaporation is the process of liquid turning into vapor. Irrigation is the artificial application of water to land. Conservation is the protection and preservation of resources. Contamination means the presence of harmful substances in something.

pH of irrigation water affects soil nutrient availability. Acidic or alkaline water can make nutrients unavailable to plants. Crop color change is not a main reason related to pH. pH does not increase soil erosion. It doesn't always help plants grow bigger.

Conservation in irrigation is about careful management. Increasing water use and wasting more water are opposite to conservation. Adding salt to water is not related to conservation.

Answer:

C. Contamination

Question 5