For a sequential reaction,

$\begin{array}{r}{\mathrm{NH}}_3⟶{\mathrm{N}}_2+{\mathrm{H}}_2 ...\left(\mathrm{i}\right)\\ {\mathrm{H}}_2+{\mathrm{O}}_2⟶{\mathrm{H}}_2\mathrm{O} ....\left(\mathrm{ii}\right)\end{array}$

What will be the amount of water which will be obtained if 5 moles of ${\mathrm{NH}}_3$ is mixed with 3 moles of ${\mathrm{O}}_2$ and % yield of 1st and 2nd reaction is 50% and 80% respectively?