Heating of 2-chloro-1-phenylbutane with EtOK/EtOH gives X as the major product. Reaction of X with Hg(OAc)₂/H₂O followed by NaBH₄ gives Y as the major product. Y is :

Consider the following reactions :

'A' is :

The ratio of number of atoms present in a simple cubic, body centered cubic and face centered cubic structure are, respectively :

In comparison to boron, berylium has :