An organic compound gives $$0.220 \mathrm{~g}$$ of $$\mathrm{CO}_{2}$$ and $$0.126 \mathrm{~g}$$ of $$\mathrm{H}_{2} \mathrm{O}$$ on complete combustion. If the $$\%$$ of carbon is 24 then the $$\%$$ of hydrogen is __________ $$\times 10^{-1}$$. ( Nearest integer)

$$\mathrm{t}_{87.5}$$ is the time required for the reaction to undergo $$87.5 \%$$ completion and $$\mathrm{t}_{50}$$ is the time required for the reaction to undergo $$50 \%$$ completion. The relation between $$\mathrm{t}_{87.5}$$ and $$\mathrm{t}_{50}$$ for a first order reaction is $$\mathrm{t}_{87.5}=x \times \mathrm{t}_{50}$$ The value of $$x$$ is ___________. (Nearest integer)

For the given reaction

The total number of possible products formed by tertiary carbocation of A is ____________.

$$20 \mathrm{~mL}$$ of calcium hydroxide was consumed when it was reacted with $$10 \mathrm{~mL}$$ of unknown solution of $$\mathrm{H}_{2} \mathrm{SO}_{4}$$. Also $$20 \mathrm{~mL}$$ standard solution of $$0.5 ~\mathrm{M} ~\mathrm{HCl}$$ containing 2 drops of phenolphthalein was titrated with calcium hydroxide, the mixture showed pink colour when burette displayed the value of $$35.5 \mathrm{~mL}$$ whereas the burette showed $$25.5 \mathrm{~mL}$$ initially. The concentration of $$\mathrm{H}_{2} \mathrm{SO}_{4}$$ is _____________ M. (Nearest integer)