Raman along with his family visited the Dead Sea. There,his father observed a lady lying on her back in the sea and reading a newspaper. This astonished Raman's father,who thought the lady might be practicing black magic. Raman explained to his father why the lady was not drowning.
$(a)$ What,according to you,is the reason the lady is not drowning in the Dead Sea?
$(b)$ What value is exhibited by Raman?

Differentiate between layers and broilers.

$(i)$ 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.

The figure shows two crop fields [Plots $A$ and $B$] that have been treated with manures and chemical fertilizers,respectively,while keeping other environmental factors constant. Observe the graph and answer the following questions.
$(i)$ Why does plot $B$ show a sudden increase and then a gradual decrease in yield?
$(ii)$ Why is the highest peak in the plot $A$ graph slightly delayed?
$(iii)$ What is the reason for the different patterns of the two graphs?

State two advantages of composite fish culture. What is the application of hormonal stimulation in fish culture?

State one importance of photoperiod in agriculture.