question ab my teachers notes !!i don’t understand how my teacher did the math to get 0.714

Explanation:
[tex]10\text{ g N2 x \lparen}\frac{1\text{ mol N2}}{28\text{ g N2}})\text{ x \lparen}\frac{2\text{ moles NH3}}{1\text{ mole N2}})\text{ = 0.714 moles NH3}[/tex]