Monomer A of a polymer on ozonolysis yields two moles of HCHO and one mole of CH$$_3$$COCHO.

(A) Deduce the structure of A.

(B) Write the structure of "all $$cis$$" forms of polymer of compound A.

Fill in the blanks:

(A) $$_{92}^{235}$$U + $$_{0}^{1}$$n $$\to$$ $$_{52}^{137}$$A + $$_{40}^{97}$$B + ____________.

(B) $$_{34}^{82}$$Se $$\to$$ 2 $${}_{ - 1}{e^0}$$ + __________.

(A) Calculate the amount of calcium oxide required to react with 852 g of P$$_4$$O$$_{10}$$.

(B) Write the structure of P$$_4$$O$$_{10}$$.

An element crystallises in fcc lattice having edge length 400 pm. Calculate the maximum diameter of the atom which can be placed in interstitial site such that the structure is not distorted.