Kemija - 2009./10. ljeto - 39.

A. $\frac{1}{2} \frac{\Delta c(\mathrm{D})}{\Delta t}$

B. $-\frac{1}{2} \frac{\Delta c(\mathrm{C})}{\Delta t}$

c. $\frac{1}{3} \frac{\Delta c(\mathrm{~A})}{\Delta t}$

D. $-\frac{1}{3} \frac{\Delta c(\mathrm{~A})}{\Delta t}$