For the Reaction of the Ammonium Ion with Nitrous Acid,the

For the reaction of the ammonium ion with nitrous acid,the net reaction is
NH₄⁺(aq) + HNO₂(aq) → N₂(g) + 2H₂O(l) + H⁺(aq)
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If the initial concentration of nitrous acid is 1.00 M and,after 17.8 s has elapsed,the concentration of nitrous acid has fallen to 0.72 M,what is the average rate of the reaction over this time interval?

A) ​-0.015 M/s
B) ​0.04 M/s
C) ​0.015 M/s
D) ​-0.04 M/s
E) ​0.096 M/s