1 mole of $$\mathrm{PbS}$$ is oxidised by "$$\mathrm{X}$$" moles of $$\mathrm{O}_3$$ to get "$$\mathrm{Y}$$" moles of $$\mathrm{O}_2$$. $$\mathrm{X}+\mathrm{Y}=$$ _________.

From the given list, the number of compounds with +4 oxidation state of Sulphur ________.

$$\mathrm{SO}_3, \mathrm{H}_2 \mathrm{SO}_3, \mathrm{SOCl}_2, \mathrm{SF}_4, \mathrm{BaSO}_4, \mathrm{H}_2 \mathrm{S}_2 \mathrm{O}_7 $$

If the formula of Borax is $$\mathrm{Na_2B_4O_x(OH)_y~.~zH_2O}$$, then $$x+y+z=$$ ___________