Why birds fly in "V-Shape" - By Kishor Singh #shorts

A bird flying in the sky has

The birds fly high in the sky due to

Why does a bird sing?

A cage of 1.5 kg carries a bird of 2.5 kg inside it. When the bird starts flying inside the cage, the weight of bird and cage assembly is

A bird weighs 2 kg and is inside a closed cage of 1 kg. If it starts flying, then what is the weight of the bird and cage assembly