Raman lives in a coastal village. He is the son of a fisherman. Whenever any unwanted animal comes in the net,instead of killing it,he puts it back in the sea.
$(a)$ What would have happened,had he killed those animals?
$(b)$ Give one reason to justify that Raman's action is environment-friendly.
$(c)$ How can you contribute to the preservation of flora and fauna around you? Mention any two steps.

Fill in the blanks:
$(a)$ $A$ total of . . . . . . nutrients are essential to plants.
$(b)$ . . . . . . and . . . . . . are supplied by air to plants.
$(c)$ . . . . . . is supplied by water to plants.
$(d)$ Soil supplies . . . . . . nutrients to plants.
$(e)$ . . . . . . nutrients are required in large quantities and are called . . . . . . .
$(f)$ . . . . . . nutrients are needed in small quantities for plants and are called . . . . . . .

$(a)$ Give two examples of shellfishes.
$(b)$ Mention the names of four marine fish of high economic value.

Which one of the following species of honey bee is an Italian species?

What are the merits and demerits of fish culture?

After combing his hair,Sameer kept the comb on the table where some pieces of paper were lying. He observed that the plastic comb attracted small pieces of paper. He was surprised to see this and asked his teacher about it. His teacher explained to Sameer that matter contains charged particles and that an electrically charged object can attract an uncharged object. Specifically,upon rubbing with dry hair,a comb acquires an electric charge,which then attracts the pieces of paper.
$(a)$ Give any other practical application of this.
$(b)$ What kind of qualities are shown by Sameer?