Fill in the blanks:
$(a)$ Pigeon pea is a good source of . . . . . . .
$(b)$ Berseem is an important . . . . . . crop.
$(c)$ The crops which are grown in the rainy season are called . . . . . . crops.
$(d)$ . . . . . . are rich in vitamins.
$(e)$ . . . . . . crop grows in the winter season.

$(i)$ What are weeds? Give two examples.
$(ii)$ "Removal of weeds from cultivated fields during the early stages of growth of crops is essential for a good harvest." Justify the statement.
$(iii)$ List five preventive methods that help in weed control.

Write three advantages of crops growing in shorter duration of time compared to those growing in longer duration of time.

"Excessive use of chemicals such as insecticides and pesticides causes a threat to ecology." Explain with reason.

List two characteristics each of roughage and concentrate in relation to animal feed. Give one example of each.

Balwinder was a small farmer. As his field was rain-fed,he could not take the risk of growing specialized crops. He used to mix the seeds of two crops and sow them in the field. Kaku,his son who passed class $IX$,suggested growing two or more crops simultaneously in a definite pattern. Balwinder followed this,and the productivity per unit area increased.
$(i)$ Name the cropping pattern which Balwinder used earlier and the one suggested by Kaku.
$(ii)$ Write two advantages of practicing the pattern suggested by Kaku.
$(iii)$ Write two values displayed by Kaku.