The total number of species from the following in which one unpaired electron is present, is _______.

$$\mathrm{N}_2, \mathrm{O}_2, \mathrm{C}_2^{-}, \mathrm{O}_2^{-}, \mathrm{O}_2^{2-}, \mathrm{H}_2^{+}, \mathrm{CN}^{-}, \mathrm{He}_2^{+}$$

Given below are two statements :

Statement I : The rate law for the reaction $$A+B \rightarrow C$$ is rate $$(r)=k[A]^2[B]$$. When the concentration of both $$\mathrm{A}$$ and $$\mathrm{B}$$ is doubled, the reaction rate is increased "$$x$$" times.

Statement II :

The figure is showing "the variation in concentration against time plot" for a "$$y$$" order reaction.

How many compounds among the following compounds show inductive, mesomeric as well as hyperconjugation effects?

When equal volume of $$1 \mathrm{~M} \mathrm{~HCl}$$ and $$1 \mathrm{~M} \mathrm{~H}_2 \mathrm{SO}_4$$ are separately neutralised by excess volume of $$1 \mathrm{M}$$ $$\mathrm{NaOH}$$ solution. $$x$$ and $$y \mathrm{~kJ}$$ of heat is liberated respectively. The value of $$y / x$$ is __________.