Does Euclid's fifth postulate imply the existence of parallel lines ? Explain.

State Euclid’s Postulate 1 and Postulate 2

l and m are two parallel lines intersected by another pair of parallel lines p and q . Show that DeltaABC~= DeltaCDA .

I and m are two parallel lines intersected by another pair of parallel lines p and show that triangle ABC = triangle CDA

How is variation necessary for existence of each species ? Explain with example.

Statement-1 : The Bohr model of the hydrogen atom does not explain the fine structure of spectral lines. and Statement-2 : The Bohr model does not take into account the spin of the electron

Why does the water rise in a capillary tube Explain .