What ability allows carbon atoms to form a large number of molecules?

Which rate indicates the number of children that would be born per woman if she were to live to the end of her child bearing years

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?

Is this correct if not can u correct me