Two friends,Girish and Neeraj,were discussing Newton's third law. They were perplexed about how action and reaction are equal and opposite. They could not think of an experiment by which they could ascertain this fact. Pushkar,who was their friend,told them that he would set up an experiment to prove this to them. By performing an experiment,Pushkar demonstrated the law.
$(a)$ Can you think of an experiment by which you can demonstrate this law?
$(b)$ What values do you think Pushkar has?

Once Ram's mother Sunita went to her friend's home along with Ram. On visiting there,Ram saw a wet khus-khus screen hung at the door of the room. He asked his mother why they had hung this screen,and his mother answered that it keeps the room cool. Ram was satisfied and smiled.
$(a)$ According to you,what qualities are possessed by Ram?
$(b)$ How does a wet khus-khus screen hung at the door keep the room cool?

Which of the following are exotic breeds of cattle?

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?

What would happen if poultry birds are larger in size and have no summer adaptation capacity? In order to get small-sized poultry birds having summer adaptability,what method will be employed?

The major groups of activities for improving crop yields can be classified as: